Device for machining oval inner wall of pump body through double-tool-rest vertical lathe

Abstract

The invention discloses a device for machining an elliptical inner wall of a pump body by using a double-tool-rest vertical lathe, which comprises a ball spline shaft assembly, a live center assembly and a turning tool fixing telescopic assembly, and the ball spline shaft assembly comprises a vertically arranged ball spline shaft body, a first ball spline sleeve and an elliptical cam; the first ball spline sleeve is arranged on the ball spline shaft body in a sleeving mode, the oval cam is fixed to the first ball spline sleeve, the lower end of the ball spline shaft body is connected with a workbench of the vertical lathe through the connecting mechanism, and the live center assembly is connected with a left tool rest of the vertical lathe and abuts against the ball spline shaft body from top to bottom. The turning tool fixing telescopic assembly comprises a sliding bottom plate, a support, a tool apron and a turning tool body and can vertically ascend and descend along with the right tool rest, when the oval cam rotates, the sliding bottom plate can telescopically move in the left-right direction, and a pump body to be machined is fixed to the center of the workbench. The problem that the elliptical inner wall of the pump body cannot be cut in the prior art is solved, and the device is low in cost and good in machining precision.

Description

Technical Field

[0001] This invention relates to the field of pump body machining, specifically to a device for machining the elliptical inner wall of a pump body using a double-tool vertical lathe. Background Technology

[0002] High-performance water ring vacuum pumps typically feature an elliptical inner wall, a key characteristic of their design. The pump body blank for water ring vacuum pumps is a cold-worked welded component. Before the machining process for the inner wall was resolved, the elliptical cylinder of the pump body was formed by rolling with a plate rolling machine or pressing point by point with a bending machine. This method failed to meet design precision, negatively impacting the performance of the vacuum pump. To address this issue, our company designed and manufactured a device for machining the elliptical inner wall of the pump body on a vertical lathe, along with corresponding processes, effectively solving this machining challenge. Summary of the Invention

[0003] This invention provides a device for machining the elliptical inner wall of a pump body using a double-tool vertical lathe, aiming to overcome the shortcomings of existing technologies where the accuracy of the elliptical inner wall of the pump body produced by cold working does not meet design requirements and there is a lack of effective mechanical equipment for cutting the elliptical inner wall of the pump body using a traditional vertical lathe.

[0004] The technical solution of the present invention to solve the above-mentioned technical problems is as follows: A device for machining the elliptical inner wall of a pump body using a double-tool post vertical lathe, comprising a ball spline shaft assembly, a live center assembly, and a tool fixing and telescopic assembly. The ball spline shaft assembly includes a vertically arranged ball spline shaft body, a first ball spline sleeve (upper ball spline sleeve), and an elliptical cam. The first ball spline sleeve is sleeved on the ball spline shaft body, and the elliptical cam is fixed on the first ball spline sleeve. The lower end of the ball spline shaft body is connected to the worktable of the vertical lathe through a connecting mechanism. The live center assembly is connected to the left tool post of the vertical lathe and presses against the ball spline shaft body from above and below. The tool fixing and telescopic assembly... The telescopic assembly includes a sliding base plate, a support, a tool holder, and a cutting tool body. The support is fixedly connected to the right tool post of the vertical lathe. The sliding base plate is slidably connected to the support. The cutting tool body is fixed to the right end of the sliding base plate via the tool holder. An elastic element is provided between the sliding base plate and the support. The elastic element causes the left end of the sliding base plate to abut against the rim of the elliptical cam. When the elliptical cam rotates, the sliding base plate can telescopically move in the left and right directions. The pump body to be processed is fixed to the worktable by a limiting clamping mechanism. When the worktable rotates, the ball spline shaft body, the elliptical cam, and the pump body to be processed all rotate synchronously around the central axis of the worktable.

[0005] Based on the above technical solution, the present invention can be further improved as follows.

[0006] Furthermore, the connecting mechanism includes a connecting base and a second ball spline bushing (lower ball spline bushing). The connecting base is fixed to the center of the worktable by a positioning plate and a locking bolt. A center hole is provided at the center of the upper end of the connecting base for the second ball spline bushing to be inserted and fixed. The lower end of the ball spline shaft body is inserted into the second ball spline bushing.

[0007] Furthermore, the connecting base includes a disc at the bottom and a cylindrical body extending upward from the center of the upper part of the disc. The second ball spline bushing is fixed inside the cylindrical body. A shaft straightening sleeve is movably sleeved on the outside of the cylindrical body. Four adjusting screws are threadedly connected to the upper part of the shaft straightening sleeve at even intervals along the circumference. A locking screw is threadedly connected to the lower part of the shaft straightening sleeve. There are four positioning pressure plates distributed at 90-degree intervals in the circumference. Each positioning pressure plate clamps and fixes the disc to the worktable by locking bolts. In other words, the upper part of the shaft straightening sleeve has four evenly distributed adjusting screws, and the lower part of the shaft straightening sleeve can be fixed to the cylindrical body on the upper part of the connecting base by locking screws (the shaft straightening sleeve is moved upward when straightening the shaft).

[0008] Furthermore, the live center assembly includes a live center position adjustment seat, a live center fixing sleeve, an externally rotating live center, a fixing bolt, and two adjusting screws. The top left side of the live center position adjustment seat is provided with a first fixing protrusion extending in a left-right direction. The left tool holder presses the first fixing protrusion with the first screw to achieve left-right adjustment (horizontal adjustment) and positioning of the live center position adjustment seat. The right side of the live center position adjustment seat has two parallel waist holes extending forward and backward. The upper part of the externally rotating live center extends into the live center fixing sleeve. The top of the live center fixing sleeve has a square outward flange. The outward flange has four fixing screw holes. The fixing bolt passes through the waist holes and is screwed into the corresponding fixing screw holes. The right side of the live center position adjustment seat has downward-facing ear plates at the front and rear ends. Both ear plates are threaded with the two adjusting screws for adjusting the front and rear position of the live center fixing sleeve.

[0009] Furthermore, a U-shaped fork is provided at the left end of the sliding base plate, and a rolling bearing is installed inside the U-shaped fork. The rim of the elliptical cam is inserted into the U-shaped fork and is in close contact with the outer ring of the rolling bearing.

[0010] Furthermore, the rolling bearing is fixed inside the U-shaped fork by a bearing mandrel that passes through the sliding base plate from top to bottom. The upper and lower parts of the bearing mandrel are respectively fixedly connected to the sliding base plate by set screws. Wear-resistant guide plates are provided on the inner wall of the U-shaped fork that contacts the upper and lower surfaces of the elliptical cam.

[0011] Furthermore, the right end of the sliding base plate is a tail plate fixedly connected to the closed end of the right side of the U-shaped fork. The tail plate is inserted into the groove of the support from the left side in a horizontal direction. The front and rear sides of the closed end of the right side of the U-shaped fork are symmetrically provided with first lugs. The front and rear sides of the left end of the support are provided with second lugs corresponding to the first lugs. The elastic element is a compression spring. The compression spring is sandwiched between the first lug and the corresponding second lug. The tail plate is also provided with multiple screw holes for connecting the lower tool holder.

[0012] Furthermore, the chute extends in the left and right direction and is located at the bottom of the support. Openings are provided at both ends of the chute and at the bottom. The support is fixedly connected with limiting pressure plates on the front and rear sides of the bottom opening of the chute to prevent the tail plate from falling out of the bottom opening of the chute.

[0013] Furthermore, a second fixing protrusion extending in the left and right direction is fixed to the top of the support, and the right tool holder is fixedly connected to the support by pressing the second fixing protrusion with a second screw; the tool holder is provided with a tool groove extending in the left and right direction, and the lathe tool body is fixed in the tool groove by a lathe tool clamping screw. A lathe tool adjusting screw is connected to the left end of the tool holder, and the left end of the lathe tool adjusting screw extends into the tool groove and abuts against the left end of the lathe tool body.

[0014] Furthermore, the pump body to be processed is fixedly connected to the worktable at its bottom by a plurality of lathe fixing jigs evenly spaced in the circumferential direction.

[0015] Compared with the prior art, the beneficial effects of the present invention are:

[0016] The device provided by this invention enables the machining of elliptical inner walls of pump bodies on a traditional double-tool vertical lathe, solving the problem of the inability to perform elliptical inner wall machining on conventional lathes. The machined elliptical inner wall exhibits good precision, fully meeting design requirements and ensuring good performance of the produced water ring pumps. The entire device has a simple structure, and its manufacturing cost is much lower than that of introducing high-precision CNC machine tools. Furthermore, this device is applicable to machining elliptical inner walls of pump bodies of different sizes, requiring only the design and replacement of corresponding sliding base plates. The device provided by this invention can also be extended to the machining of irregularly shaped inner walls with smooth transitions, demonstrating good applicability. Attached Figure Description

[0017] Figure 1 A schematic diagram of the device provided by the present invention for machining the elliptical inner wall of a pump body using a double-tool vertical lathe;

[0018] Figure 2 for Figure 1 Top view of the device shown (left and right tool holders and live center assembly not shown);

[0019] Figure 3 for Figure 1 A schematic diagram of the left-middle tool holder and the live center assembly in the device shown, viewed along direction A;

[0020] Figure 4 for Figure 1 A schematic diagram showing some components of the lower structure of the device after being cut open.

[0021] Figure 5 for Figure 4 The structure shown is a cross-sectional view along BB;

[0022] Figure 6 for Figure 1 Front and top views of the center-mounted top position adjustment seat;

[0023] Figure 7 for Figure 1 Top view and vertical sectional view of the center live center fixing sleeve;

[0024] Figure 8 for Figure 1 Front view of the center and outer rotating tip;

[0025] Figure 9 for Figure 1 Half-section view and top view of the sliding base plate;

[0026] Figure 10 for Figure 1 Three views of the central support;

[0027] Figure 11 for Figure 1 Front view, left view and sectional view along CC of the middle tool holder;

[0028] Figure 12 for Figure 1 Top view and sectional view along the major axis of the elliptical cam.

[0029] The attached diagram lists the components represented by each number as follows:

[0030] 1. Ball spline shaft body; 2. First ball spline sleeve; 3. Elliptical cam; 4. Worktable; 5. Left tool post; 6. Sliding base plate; 7. Support; 8. Tool holder; 9. Lathe tool body; 10. Right tool post; 11. Pump body to be machined; 12. Connecting base; 13. Second ball spline shaft sleeve; 14. Positioning pressure plate; 15. Shaft straightening sleeve; 16. Adjusting screw one; 17. Straightening sleeve locking screw; 18. Adjustable top 19. Point position adjustment seat; 20. Live center fixing sleeve; 21. Externally rotated live center; 22. Adjusting screw two; 23. First fixing convex strip; 24. Outward flange; 25. Waist hole; 26. Rolling bearing; 27. Bearing spindle; 28. Wear-resistant guide plate; 29. ​​Slide groove; 30. Compression spring; 31. Limiting pressure plate; 32. Second fixing convex strip; 33. Tool groove; 34. Lathe tool adjusting screw; 35. Lathe fixed fixture. Detailed Implementation

[0031] The technical solutions provided by the present invention will be clearly and completely described below with reference to the accompanying drawings and specific embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0032] In the description of this invention, if terms such as "upper," "lower," "left," "right," "top," "bottom," "inner," and "outer" are used to indicate the orientation or positional relationship, the orientation or positional relationship indicated is based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0033] like Figures 1 to 12As shown, this invention provides a device for machining the elliptical inner wall of a pump body using a double-tool-post vertical lathe. The device includes a ball spline shaft assembly, a live center assembly, and a tool fixing and telescopic assembly. The ball spline shaft assembly includes a vertically arranged ball spline shaft body 1, a first ball spline sleeve 2, and an elliptical cam 3. The first ball spline sleeve 2 is fitted onto the ball spline shaft body 1, and the elliptical cam 3 is fixed to the first ball spline sleeve 2. The lower end of the ball spline shaft body 1 is connected to the worktable 4 of the vertical lathe via a connecting mechanism. The live center assembly is connected to the left tool post 5 of the vertical lathe and presses against the ball spline shaft body 1 from above. The tool fixing and telescopic assembly includes a sliding base plate 6, a support 7, and a tool. The lathe includes a support 8 and a tool body 9. The support 7 is fixedly connected to the right tool post 10 of the vertical lathe. The sliding base plate 6 is slidably connected to the support 7. The tool body 9 is fixed to the right end of the sliding base plate 6 via the tool holder 8. An elastic element is provided between the sliding base plate 6 and the support 7. The elastic element causes the left end of the sliding base plate 6 to abut against the rim of the elliptical cam 3. When the elliptical cam 3 rotates, the sliding base plate 6 can extend and retract in the left and right directions. The pump body 11 to be processed is fixed on the worktable 4 by a limiting clamping mechanism. When the worktable 4 rotates, the ball spline shaft body 1, the elliptical cam 3, and the pump body 11 to be processed all rotate synchronously around the central axis of the worktable 4.

[0034] It should be noted that the pump body (workpiece) to be processed is a cold-worked welded part, and the inner wall of its blank is already approximately elliptical. At the same time, before using the device provided by this invention to process the elliptical inner wall of the pump body, the flanges at both ends of the pump body have been processed.

[0035] When the worktable of the vertical lathe rotates, the connecting structure (ball spline shaft base and lower ball spline bushing) installed at the center of the worktable drives the ball spline shaft body to rotate synchronously. The ball spline shaft body rotates synchronously through the elliptical cam driven by the upper ball spline bushing. At the same time, the worktable also drives the pump body to be machined to rotate synchronously with the worktable. The elliptical cam pushes the sliding base plate to extend and retract through the ball bearings close to its outer circle (due to the cutting force of the cutting tool body and the compression spring). The tool holder and cutting tool body installed on the sliding base plate also move accordingly (the cutting tool body extends and retracts once for every 360° rotation of the pump body). In this way, an elliptical circle can be machined on the inner wall of the pump body. The difference between the major and minor axes of the ellipse on the inner wall of the pump body is equal to the difference between the major and minor axes of the elliptical cam. The right tool post of the vertical lathe, through the support and sliding base plate, drives the cutting tool body, the elliptical cam, and the upper ball spline bushing to move up and down along the ball spline shaft body, completing the automatic tool feed. This completes one full cutting operation on the inner wall of the pump body. Adjusting the tool extension length using the tool adjusting screw on the left end of the tool holder and repeating the cutting process 2-4 times will complete the cutting operation on the inner wall of the pump body.

[0036] In one embodiment of the present invention, such as Figure 1 and Figure 4 As shown, the connecting mechanism includes a connecting base 12 and a second ball spline bushing 13. The connecting base 12 is fixed to the center of the worktable 4 by a positioning pressure plate 14 and a locking bolt. The upper center of the connecting base 12 has a central hole for the second ball spline bushing 13 to be inserted and fixed. The lower end of the ball spline shaft body 1 is inserted into the second ball spline bushing 13.

[0037] It should be noted that the first and second ball spline bushings can rotate synchronously with the ball spline shaft body (i.e., they can transmit torque). In practice, when the worktable rotates, the connecting base drives the second ball spline bushing to rotate synchronously, which in turn drives the ball spline shaft body to rotate synchronously. The ball spline shaft body then drives the elliptical cam to rotate synchronously via the first ball spline bushing. The first ball spline bushing can move vertically along the ball spline shaft body, and the driving force for this movement is transmitted from the right tool post of the vertical lathe through the support and sliding base plate. The second ball spline bushing is fixedly connected to the connecting base with multiple bolts. Simultaneously, after the ball spline shaft body is inserted into the second ball spline bushing, its lower end presses the connecting base firmly onto the worktable.

[0038] In one embodiment of the present invention, such as Figure 1 and 4 As shown, the connecting base 12 includes a disc at the bottom and a cylindrical body extending upward from the center of the upper part of the disc. The second ball spline bushing 13 is fixed inside the cylindrical body. A shaft straightening sleeve 15 is movably sleeved on the outside of the cylindrical body. Four adjusting screws 16 are threadedly connected to the upper part of the shaft straightening sleeve 15 at even intervals along the circumference. A straightening sleeve locking screw 17 is threadedly connected to the lower part of the shaft straightening sleeve 15. There are four positioning pressure plates 14, which are distributed at 90-degree intervals in the circumference. Each positioning pressure plate 14 clamps and fixes the disc to the worktable 4 by locking bolts.

[0039] It should be noted that the shaft straightening sleeve is loosely fitted onto the cylindrical body, meaning that when the straightening sleeve locking screw is not tightened, the shaft straightening sleeve can reciprocate vertically relative to the cylindrical body. When straightening the ball spline shaft body is required, the shaft straightening sleeve can be moved upwards a certain distance, and then locked onto the cylindrical body using the straightening sleeve locking screw. This allows the adjusting screws at the top to push the ball spline shaft body to swing slightly when tightened. After the fine-tuning and straightening of the ball spline shaft body is completed, the live center assembly presses down to press and position the ball spline shaft. At this point, to prevent the shaft straightening sleeve from affecting the operation of the device, the straightening sleeve locking screw can be loosened to allow the shaft straightening sleeve to fall back to the standby state. Figure 4As shown, the shaft straightening sleeve is in its ready-to-use state at this time. When it is needed, the shaft straightening sleeve needs to be moved up and lifted again. The purpose of this setting is to minimize the bottom height of the workpiece.

[0040] In one embodiment of the present invention, such as Figure 1 , 3 As shown in Figures 6-8, the live center assembly includes a live center position adjustment seat 18, a live center fixing sleeve 19, an externally rotating live center 20, a fixing bolt, and an adjusting screw 21. The top left side of the live center position adjustment seat 18 is provided with a first fixing protrusion 22 extending in a left-right direction. The left tool holder 5 achieves horizontal adjustment and positioning of the live center position adjustment seat 18 by pressing the first fixing protrusion 22 with the first screw. The right side of the live center position adjustment seat 18 has two parallel waist holes 24 extending forward and backward. The upper part of the externally rotating live center 20 extends into the live center fixing sleeve 19. The top of the live center fixing sleeve 19 has a square outward flange 23 with four fixing screw holes. The fixing bolt passes through the waist hole 24 and is screwed into the fixing screw hole. The right side of the live center position adjustment seat 18 has downward-facing ear plates at both ends. The forward and backward position of the live center fixing sleeve can be adjusted by adjusting screws on the two ear plates.

[0041] It should be noted that the left tool post of the vertical lathe can provide vertical clamping force to the ball spline shaft body through the live center assembly, keeping the ball spline shaft body coaxial with the center line of the vertical lathe table.

[0042] In one embodiment of the present invention, a U-shaped fork is provided at the left end of the sliding base plate 6, and a rolling bearing 25 is installed inside the U-shaped fork. The rim of the elliptical cam 3 is inserted into the U-shaped fork and is in close contact with the outer ring of the rolling bearing 25.

[0043] It should be noted that the U-shaped fork of the sliding base plate functions similarly to a shift fork. When the right tool of the vertical lathe drives the support and the sliding base plate to rise and fall vertically, the U-shaped fork can drive the elliptical cam inserted within it to rise and fall synchronously. Since the elliptical cam is integrated with the first ball spline bushing, the first ball spline bushing also rises and falls accordingly. The rolling bearing enables rolling friction between the cylindrical surface of the elliptical cam rim and the sliding base plate, reducing frictional resistance and wear, and enhancing durability.

[0044] In one embodiment of the present invention, the rolling bearing 25 is fixed in the U-shaped fork by a bearing spindle 26 that passes through the sliding base plate 6 from top to bottom. The upper and lower parts of the bearing spindle 26 are respectively fixedly connected to the sliding base plate 6 by set screws. A wear-resistant guide plate 27 is provided on the inner wall of the U-shaped fork that contacts the upper and lower surfaces of the elliptical cam 3.

[0045] It should be noted that, as Figure 4 As shown, two stacked rolling bearings are installed inside the U-shaped fork, with the outer rings of both bearings effectively contacting the cylindrical surface of the elliptical cam rim. To ensure a tighter fit between the outer rings of the two deep groove ball bearings (rolling bearings) and the elliptical cam (part 21), in addition to using two compression springs, the bearings are selected with P5 precision. Furthermore, a washer can be added between the inner rings of the two bearings, allowing the bearing clearance to further tighten the fit between the outer rings of the two bearings and the outer ring of the elliptical cam. To reduce sliding friction and wear between the inner wall of the sliding base plate fork and the horizontal surface of the elliptical cam rim, a wear-resistant guide plate is specifically attached to the fork area of ​​the sliding base plate.

[0046] In one embodiment of the present invention, such as Figure 4 and Figure 9 As shown, the right end of the sliding base plate 6 is a tail plate fixedly connected to the right closed end of the U-shaped fork. The tail plate is inserted into the sliding groove 28 of the support 7 from the left side in a horizontal direction. The front and rear sides of the right closed end of the U-shaped fork are symmetrically provided with first lugs. The front and rear sides of the left end of the support 7 are provided with second lugs corresponding to the first lugs. The elastic element is a compression spring 29. The compression spring 29 is sandwiched between the first lug and the corresponding second lug. The tail plate is also provided with multiple screw holes for connecting the lower knife holder 8.

[0047] It should be noted that the compression spring 29 is always in a compressed state, which ensures that the outer ring of the rolling bearing inside the U-shaped fork of the sliding base plate is always pressed against the cylindrical surface of the elliptical cam wheel rim.

[0048] In one embodiment of the present invention, the slide 28 extends in the left and right direction and is located at the bottom of the support 7. The left and right ends and the bottom of the slide 28 are provided with openings. The support 7 is fixedly connected with limiting pressure plates 30 on the front and rear sides of the bottom opening of the slide 28 to prevent the tail plate from falling out of the bottom opening of the slide 28.

[0049] It is understandable that, such as Figure 5 and Figure 10 As shown, the limiting pressure plate can be connected to the support by bolts. In order to reduce the friction between the sliding bottom plate tail plate and the chute wall, a wear-resistant guide plate and a lubricating oil groove are provided on the inner wall of the chute, and a pressure-injection lubricating oil cup is also installed.

[0050] In one embodiment of the present invention, such as Figure 5 and 11As shown, the support 7 has a second fixing protrusion 31 extending from left to right fixed on its top. The right tool holder 10 is fixed to the support 7 by pressing the second fixing protrusion 31 with a second screw. The tool holder 8 has a tool groove 32 extending from left to right. The lathe tool body 9 is fixed in the tool groove 32 by a lathe tool clamping screw. The left end of the tool holder 8 is connected to a lathe tool adjusting screw 33. The left end of the lathe tool adjusting screw 33 extends into the tool groove 32 and abuts against the left end of the lathe tool body 9.

[0051] In one embodiment of the present invention, such as Figure 1 and 2 As shown, the pump body 11 to be processed is fixedly connected to the worktable 4 at its bottom by a plurality of lathe fixing jigs 34 evenly spaced in the circumferential direction.

[0052] It should be noted that in the above embodiments, the ball spline shaft body is subjected to radial pressure from two compression springs and the cutting force of the cutting tool during operation. In order to reduce this pressure and prevent the spline shaft from bending and affecting the straightness of the generatrix of the pump body, the principal cutting edge angle of the cutting tool must not be less than 75º. After calculation and machining verification, the deformation of the ball spline shaft caused by the above two forces is much smaller than the allowable straightness tolerance of the generatrix.

[0053] When using the device provided by this invention to process the elliptical inner wall of the pump body, the following installation and calibration work needs to be done first:

[0054] 1) After placing the pump body workpiece to be processed onto the automotive jig on the workbench, the pump body must be manually rotated so that the major axis of the pump body inner wall coincides with the major axis of the elliptical cam, and then the pump body is pressed tightly.

[0055] 2) The rotation and lifting of the elliptical cam in this device rely on the ball spline shaft body and bushing components. This component can accurately transmit torque and also allow the parts it drives to move axially relatively easily and smoothly.

[0056] 3) In this invention, ensuring that the centerline of the ball spline shaft body coincides with the centerline of the vertical lathe spindle (worktable centerline) is a crucial problem to solve. Typically, the lower part of the ball spline shaft body coincides with the centerline of the vertical lathe spindle. The key to aligning the entire shaft with the vertical lathe centerline is to ensure the centerline of the upper external rotating live center coincides with the centerline of the vertical lathe spindle. Therefore, this device includes a shaft alignment sleeve at the lower part of the ball spline shaft body and a live center position adjustment seat at the upper part of the ball spline shaft body. The steps to align the centerlines are as follows: a. After moving the shaft alignment sleeve upwards, use the screws at the bottom of the shaft alignment sleeve to fix it to the ball spline shaft base. When tightened, the four adjusting screws should directly contact the ball spline body. b. Install the live center position adjusting seat and live center fixing sleeve onto the left tool post of the vertical lathe. Ensure it is leveled using a level, with a deviation less than 0.10 / 1000. Then install a dial indicator. c. Jog the vertical lathe worktable and use a dial indicator to check the runout at the top of the ball spline shaft. Simultaneously, adjust the four adjusting screws located on the lower part of the shaft alignment sleeve to ensure the runout at the top of the ball spline shaft is less than 0.04, and then fix it. d. Adjust the alignment of the live centerline with the centerline of the vertical lathe spindle by moving the left and right tool post of the vertical lathe and the live center fixing sleeve back and forth. For coarse adjustment, a knife-edge ruler can be used to measure (the outer diameter of the live center retaining sleeve should match the outer diameter of the ball spline shaft). After coarse adjustment, install the external rotating live center and place a dial indicator on it. Use the dial indicator method to check the coincidence of their center lines. e. After adjustment, fix the adjustable parts and recheck the coincidence using the dial indicator method. Once confirmed to be in good condition (the dial indicator runout is less than 0.05), use the live center to firmly hold the spline shaft. At this point, the center line coincidence adjustment is complete.

[0057] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A device for machining the elliptical inner wall of a pump body using a double-tool vertical lathe, characterized in that, The lathe includes a ball spline shaft assembly, a live center assembly, and a tool fixing and telescopic assembly. The ball spline shaft assembly includes a vertically arranged ball spline shaft body (1), a first ball spline sleeve (2), and an elliptical cam (3). The first ball spline sleeve (2) is fitted onto the ball spline shaft body (1), and the elliptical cam (3) is fixed onto the first ball spline sleeve (2). The lower end of the ball spline shaft body (1) is connected to the worktable (4) of the vertical lathe via a connecting mechanism. The live center assembly is connected to the left tool post (5) of the vertical lathe and presses against the ball spline shaft body (1) from above. The tool fixing and telescopic assembly includes a sliding base plate (6), a support (7), a tool holder (8), and a tool body (9). The support (7) is connected to the worktable (4) of the vertical lathe. The right tool post (10) of the lathe is fixedly connected, the sliding base plate (6) is slidably connected to the support (7), the cutting tool body (9) is fixed to the right end of the sliding base plate (6) through the tool holder (8), an elastic element is provided between the sliding base plate (6) and the support (7), the elastic element makes the left end of the sliding base plate (6) abut against the rim of the elliptical cam (3), when the elliptical cam (3) rotates, the sliding base plate (6) can move in the left and right directions, the pump body (11) to be processed is fixed on the worktable (4) through the limiting clamping mechanism, when the worktable (4) rotates, the ball spline shaft body (1), the elliptical cam (3) and the pump body (11) to be processed all rotate synchronously around the central axis of the worktable (4).

2. The apparatus for machining the elliptical inner wall of a pump body using a double-tool post vertical lathe according to claim 1, characterized in that, The connecting mechanism includes a connecting base (12) and a second ball spline bushing (13). The connecting base (12) is fixed to the center of the worktable (4) by a positioning plate (14) and a locking bolt. The upper center of the connecting base (12) has a central hole for the second ball spline bushing (13) to be inserted and fixed. The lower end of the ball spline shaft body (1) is inserted into the second ball spline bushing (13).

3. The apparatus for machining the elliptical inner wall of a pump body using a double-tool post vertical lathe according to claim 2, characterized in that, The connecting base (12) includes a disc at the bottom and a cylindrical body extending upward from the center of the upper part of the disc. The second ball spline bushing (13) is fixed inside the cylindrical body. A shaft straightening sleeve (15) is movably sleeved on the outside of the cylindrical body. Four adjusting screws (16) are threadedly connected to the upper part of the shaft straightening sleeve (15) at even intervals along the circumference. A straightening sleeve locking screw (17) is threadedly connected to the lower part of the shaft straightening sleeve (15). There are four positioning pressure plates (14) and they are distributed at 90-degree intervals along the circumference. Each positioning pressure plate (14) clamps and fixes the disc to the worktable (4) by locking bolts.

4. The apparatus for machining the elliptical inner wall of a pump body using a double-tool post vertical lathe according to claim 1, characterized in that, The live center assembly includes a live center position adjustment seat (18), a live center fixing sleeve (19), an external rotating live center (20), a fixing bolt, and an adjusting screw (21). The top left side of the live center position adjustment seat (18) is provided with a first fixing protrusion (22) extending in the left and right directions. The left tool holder (5) presses the first fixing protrusion (22) with the first screw to achieve horizontal adjustment and positioning of the live center position adjustment seat (18). The right side of the live center position adjustment seat (18) is provided with two parallel waist holes (24) extending forward and backward. The upper part of the external rotating live center (20) extends into the live center fixing sleeve (19). The top of the live center fixing sleeve (19) has a square outward flange (23). The outward flange (23) is provided with four fixing screw holes. The fixing bolt passes through the waist hole (24) and is screwed into the fixing screw hole. The front and rear ends of the right side of the live center position adjustment seat (18) are provided with downward-facing ear plates. The adjusting screw (21) is threadedly connected to both ear plates.

5. The apparatus for machining the elliptical inner wall of a pump body using a double-tool post vertical lathe according to claim 1, characterized in that, The left end of the sliding base plate (6) is provided with a U-shaped fork, and a rolling bearing (25) is installed in the U-shaped fork. The rim of the elliptical cam (3) is inserted into the U-shaped fork and is in close contact with the outer ring of the rolling bearing (25).

6. The apparatus for machining the elliptical inner wall of a pump body using a double-tool post vertical lathe according to claim 5, characterized in that, The rolling bearing (25) is fixed in the U-shaped fork by a bearing spindle (26) that passes through the sliding base plate (6) from top to bottom. The upper and lower parts of the bearing spindle (26) are fixedly connected to the sliding base plate (6) by set screws. Wear-resistant guide plates (27) are provided on the inner wall of the U-shaped fork that contacts the upper and lower surfaces of the elliptical cam (3).

7. The apparatus for machining the elliptical inner wall of a pump body using a double-tool post vertical lathe according to claim 5, characterized in that, The right end of the sliding base plate (6) is a tail plate fixedly connected to the right closed end of the U-shaped fork. The tail plate is inserted into the groove (28) of the support (7) from the left side in a horizontal direction. The front and rear sides of the right closed end of the U-shaped fork are symmetrically provided with first lugs. The front and rear sides of the left end of the support (7) are provided with second lugs corresponding to the first lugs. The elastic element is a compression spring (29). The compression spring (29) is sandwiched between the first lug and the corresponding second lug. The tail plate is also provided with multiple screw holes for connecting the lower knife holder (8).

8. The apparatus for machining the elliptical inner wall of a pump body using a double-tool post vertical lathe according to claim 7, characterized in that, The slide (28) extends in the left and right direction and is located at the bottom of the support (7). The left and right ends and the bottom of the slide (28) are provided with openings. The support (7) is fixedly connected to the front and rear sides of the bottom opening of the slide (28) with limiting pressure plates (30) to prevent the tail plate from falling out of the bottom opening of the slide (28).

9. The apparatus for machining the elliptical inner wall of a pump body using a double-tool post vertical lathe according to claim 1, characterized in that, The support (7) is fixed with a second fixed protrusion (31) extending in the left and right directions. The right tool holder (10) is fixed to the support (7) by pressing the second fixed protrusion (31) with a second screw. The tool holder (8) is provided with a tool groove (32) extending in the left and right directions. The cutting tool body (9) is fixed in the tool groove (32) by a cutting tool clamping screw. The left end of the tool holder (8) is connected to a cutting tool adjusting screw (33). The left end of the cutting tool adjusting screw (33) extends into the tool groove (32) and abuts against the left end of the cutting tool body (9).

10. A device for machining the elliptical inner wall of a pump body using a double-tool post vertical lathe according to any one of claims 1 to 9, characterized in that, The pump body (11) to be processed is fixedly connected to the worktable (4) at its bottom by a plurality of lathe fixing jigs (34) evenly spaced in the circumferential direction.

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