A turning device for a motor shaft

Abstract

This invention provides a turning device for motor shafts, belonging to the field of turning machine tool technology. The invention includes a machine tool bed, a movable frame mounted on the machine tool bed, a support and chip-blowing assembly, and a pneumatic vibration assembly. The support and chip-blowing assembly is located on one side of the movable frame and is used to provide follow-up support for the motor shaft to be machined, while simultaneously blowing away turning chips. The pneumatic vibration assembly is located on the support and chip-blowing assembly and is used to eliminate stress generated during cutting of the surface of the motor shaft. This invention achieves effective suppression of chatter during the turning of slender motor shafts by fixing the support and chip-blowing assembly to the movable frame and enabling the support point to move synchronously with the tool. By integrating the pneumatic vibration assembly inside the slider, high-frequency micro-amplitude vibration is generated using fluid drive and transmitted to the surface of the motor shaft via ball bearings, achieving online elimination of residual stress. By changing the installation orientation of the mounting cavity, the resultant vibration force can be switched to either pass through the shaft center, adapting to the stress elimination requirements of different machining stages.

Description

Technical Field

[0001] This invention relates to the field of turning machine tool technology, and more specifically, to a turning apparatus for a motor shaft. Background Technology

[0002] Motor shafts are key transmission components in motor systems, and their production requires specialized turning equipment. This type of equipment achieves high-precision, high-efficiency turning of motor shaft parts through the coordinated motion of workpiece rotation and tool movement, combined with a high-rigidity structure, precision feed system, and intelligent control technology. It is an important component of the intelligent manufacturing equipment industry.

[0003] In the turning process of motor shafts, especially for slender motor shafts (length-to-diameter ratio greater than 10), traditional machining equipment typically uses a three-jaw chuck to hold one end and a tailstock center to hold the other end. This method presents the following technical problems: slender motor shafts are prone to tool deflection and chatter under cutting forces, affecting cylindricity and surface quality, and in severe cases, even leading to scrap. Turning introduces residual tensile stress on the surface of the motor shaft. If not removed, this will lead to deformation and reduced fatigue life during subsequent use. Traditional stress relief methods (such as thermal aging and vibration aging) require separate processes, increasing production cycle and cost. In addition, chips generated during turning are prone to entanglement on the tool or workpiece, affecting the surface quality of the machined material, while the accumulation of cutting heat leads to a decrease in tool life.

[0004] To address the aforementioned problems, while existing technologies employ center supports for auxiliary support, these are mostly fixed center supports with support points far from the cutting area, resulting in limited vibration suppression. Furthermore, existing devices lack the function of simultaneously eliminating residual stress during machining. Therefore, providing a motor shaft turning device capable of achieving follow-up support, online stress elimination, and efficient chip removal during turning has become a pressing technical problem for those skilled in the art. Summary of the Invention

[0005] To overcome the above deficiencies, the present invention provides a turning apparatus for motor shafts, which aims to solve the problems mentioned in the background.

[0006] This invention is implemented as follows:

[0007] This invention provides a turning apparatus for a motor shaft, including a machine tool bed, a movable frame mounted on the machine tool bed, and further comprising:

[0008] The chip blowing assembly is located on one side of the movable frame and is used to provide follow-up support for the motor shaft to be processed, while also blowing away turning chips.

[0009] A pneumatic vibration assembly, mounted on the support chip blowing assembly, is used to eliminate the stress generated during the cutting of the surface of the motor shaft to be processed.

[0010] Preferably, the machine tool bed is provided with a first feed mechanism and a second feed mechanism on its side. A machine tool tailstock is also slidably connected to the machine tool bed. A first drive device is installed on the machine tool bed, and a second drive device is installed on the machine tool tailstock. Both the first and second drive devices have chucks at their output ends. The output ends of the first and second feed mechanisms are connected to lead screws. The lead screw on the first feed mechanism is threadedly connected to the moving frame, and the lead screw on the second feed mechanism is threadedly connected to the machine tool tailstock. A tool post base is slidably connected to the moving frame. A tool turret mechanism is installed on the tool post base. The output end of the tool turret mechanism has a turret tool post. A cutting fluid spray pipe is inserted into one side of the tool post base. A machine tool shell is provided on the outside of the machine tool bed.

[0011] Preferably, the supporting chip removal assembly includes a mounting base fixedly connected to a movable frame, a support base fixedly connected to the end of the mounting base, a positioning ring fixedly connected to the upper end of the support base, and multiple radial cavities evenly distributed along the circumference of the positioning ring; a slider is slidably connected within the radial cavities, and the slider and the inner cavity of the radial cavities are elastically connected by a spring; an electromagnet for controlling the slider to reset is installed on the inner side of the radial cavities, and a ball bearing is rotatably engaged at the end of the slider away from the electromagnet; a guide channel penetrating the side wall of the slider is provided inside the slider, and an oblique spray pipe is connected through the end of the guide channel.

[0012] Preferably, the positioning ring is coaxially arranged with the motor shaft to be processed, the support base has a transmission channel inside, the positioning ring has an annular channel inside, the multiple radial cavities are connected through the annular channel, the upper end of the transmission channel is connected to the annular channel, the lower end of the transmission channel penetrates the side wall of the support base, and a quick connector is installed at the lower end of the transmission channel, which is connected to an external power supply pipeline.

[0013] Preferably, the angle between the spray axis of the inclined nozzle and the axis of the motor shaft to be processed is 30° to 60°, and its spray direction is directed towards the cutting area of ​​the tool; the top of the slider has an inclined groove for the guide channel, and the top of the guide channel has a flow groove.

[0014] Preferably, when the device is in the turning process, the electromagnet is de-energized, and the spring pushes the slider to press the ball against the surface of the motor shaft to be processed, while the fluid is sprayed out through the oblique nozzle; when it is necessary to move the frame to quickly retract the tool, the electromagnet is energized, overcoming the spring force to pull the slider back to its original position, so that the ball is removed from the surface of the motor shaft to be processed.

[0015] Preferably, the pneumatic vibration assembly includes a mounting cavity and a movable cavity. The mounting cavity is located beside and communicates with the guide channel. A rotating wheel assembly is rotatably connected inside the mounting cavity. A movable rod is slidably connected inside the movable cavity. One end of the movable rod passes through the side wall of the mounting cavity and extends into the mounting cavity, while the other end passes through the outer wall of the slider and extends out of the slider. A limiting plate is fixedly connected to the movable rod located inside the movable cavity. The limiting plate is elastically connected to the inner wall of the movable cavity by a spring. The end of the movable rod located inside the mounting cavity is provided with a dome, and a connecting block is fixedly connected to the end of the movable rod located outside the slider.

[0016] Preferably, the movable cavity is inclined, and the placement cavity is parallel to the movable cavity; when the second spring is in the initial state, the limiting plate abuts against the end of the movable cavity, and the side wall of the connecting block abuts against the outer side wall of the slider;

[0017] With the feed direction of the tool as a reference, when the axis of the mounting cavity is perpendicular to the feed direction of the tool, the resultant force of the vibration generated by the limiting plate and the connecting block passes through the axis of the motor shaft to be processed; when the axis of the mounting cavity is parallel to the feed direction of the tool, the resultant force of the vibration generated by the limiting plate and the connecting block does not pass through the axis of the motor shaft to be processed.

[0018] Preferably, the rotating wheel assembly is provided with alternating long arc plates and short arc plates, and the ends of the long arc plates and short arc plates are both arc-shaped.

[0019] Preferably, when the fluid passes through the guide channel, the fluid drives the rotating wheel assembly to rotate; when the second spring is in the initial state, the dome is located between the long arc plate and the short arc plate's movement trajectory, so that the end of the long arc plate can contact the dome, while the end of the short arc plate does not contact the dome.

[0020] The beneficial effects of this invention are:

[0021] 1. The present invention fixes the chip blowing support assembly to one side of the moving frame, so that it moves axially synchronously with the tool. The support point is always close to the cutting area. Compared with the fixed center frame, the follow-up support of the present invention can provide effective radial stiffness compensation for the slender motor shaft, reduce tool deflection and chatter, and improve machining accuracy and surface quality.

[0022] 2. This invention integrates a pneumatic vibration component inside the slider, utilizing the fluid (compressed air or cutting fluid) already present during turning as a power source to drive the rotating wheel assembly to rotate, generating high-frequency micro-amplitude vibrations that are transmitted to the motor shaft surface via ball bearings. This vibration effectively eliminates residual tensile stress introduced by turning, eliminating the need for additional thermal or vibration aging processes and significantly shortening the production cycle. By changing the installation orientation of the mounting cavity, the resultant vibration force can selectively pass through or not through the shaft center: when the resultant force passes through the shaft center, it generates pure radial pulsating pressure, suitable for chatter suppression and uniform stress elimination during the finishing stage; when the resultant force does not pass through the shaft center, it generates eccentric torque and alternating bending stress, which can activate the multiple slip systems within the material, resulting in better elimination of large residual stress after rough machining. Users can flexibly select or combine configurations according to the machining stage and the motor shaft material.

[0023] 3. The angled nozzle is directed at the cutting area of ​​the tool at an angle of 30° to 60°, and the sprayed fluid simultaneously achieves chip removal, cooling and cleaning of the ball contact area; it works in coordination with the cutting fluid nozzle to achieve all-round cooling and chip removal coverage. Since the motor shaft is rotating, the fluid can repeatedly flush the entire circumferential contact zone from different angles, resulting in a significant dynamic cleaning effect. Attached Figure Description

[0024] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained from these drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0026] Figure 2 This is a schematic diagram of the internal structure of the machine tool housing according to the present invention;

[0027] Figure 3 This is a schematic diagram of the movable frame and tool holder base structure of the present invention;

[0028] Figure 4 This is a schematic diagram of the cross-sectional structure of the machine tool according to the present invention;

[0029] Figure 5 This is a schematic diagram of the installation position of the chip removal assembly of the present invention;

[0030] Figure 6 This is a schematic diagram of the internal structure of the chip removal support assembly of the present invention;

[0031] Figure 7 This is a schematic diagram of the placement structure of the motor shaft to be processed according to the present invention;

[0032] Figure 8 This is a schematic diagram of the overall structure of the chip removal support assembly of the present invention;

[0033] Figure 9 This is a schematic cross-sectional view of the structure of the long arc plate of the present invention when it comes into contact with the dome;

[0034] Figure 10 This is the invention Figure 9 Enlarged structural diagram at point A in the middle;

[0035] Figure 11 This is a schematic diagram of the cross-sectional structure of the slider of the present invention;

[0036] Figure 12 This is a schematic diagram showing the direction of the resultant force of the vibration generated by the limiting plate and connecting block of the present invention (at which time the mounting cavity is located in the ZOY plane).

[0037] In the diagram: 1. Machine bed; 2. Drive unit one; 3. First feed mechanism; 4. Second feed mechanism; 5. Mounting base; 6. Support base; 7. Positioning ring; 8. Slider; 9. Moving rod; 10. Machine housing; 21. Chuck; 31. Moving frame; 32. Tool post base; 33. Tool turning mechanism; 34. Turret tool post; 35. Coolant spray nozzle; 41. Machine tailstock; 42. Drive unit two; 61. Transmission Channel; 62. Annular channel; 63. Quick connector; 71. Radial cavity; 72. Spring 1; 73. Electromagnet; 80. Inclined groove; 81. Ball bearing; 82. Guide channel; 83. Inclined nozzle; 84. Installation cavity; 85. Rotary wheel assembly; 90. Movable cavity; 91. Limiting plate; 92. Connecting block; 93. Dome; 94. Spring 2; 801. Drainage groove; 851. Long arc plate; 852. Short arc plate. Detailed Implementation

[0038] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, 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.

[0039] Example 1, refer to Figures 1-11 A turning apparatus for a motor shaft includes a machine bed 1, a movable frame 31 mounted on the machine bed 1, and further includes:

[0040] The chip blowing assembly is located on one side of the movable frame 31 and is used to provide follow-up support for the motor shaft to be processed, while also blowing away turning chips.

[0041] A pneumatic vibration assembly, mounted on the support chip blowing assembly, is used to eliminate the stress generated during the cutting of the surface of the motor shaft to be processed.

[0042] Furthermore, a first feed mechanism 3 and a second feed mechanism 4 are provided on the side of the machine tool bed 1. A machine tool tailstock 41 is also slidably connected to the machine tool bed 1. A drive device 1 2 is installed on the machine tool bed 1, and a drive device 2 42 is installed on the machine tool tailstock 41. Both the output ends of the drive device 1 2 and the drive device 2 42 are provided with chucks 21. The output ends of the first feed mechanism 3 and the second feed mechanism 4 are both connected with lead screws. The lead screw on the first feed mechanism 3 is threadedly connected to the moving frame 31, and the lead screw on the second feed mechanism 4 is threadedly connected to the machine tool tailstock 41. A tool post base 32 is slidably connected to the moving frame 31. A tool turning mechanism 33 is installed on the tool post base 32. A turret tool post 34 is provided at the output end of the tool turning mechanism 33. A cutting fluid spray pipe 35 is inserted into one side of the tool post base 32 to provide cutting fluid for cooling and lubricating the cutting area. A machine tool shell 10 is provided on the outside of the machine tool bed 1.

[0043] The support chip-blowing assembly (angled nozzle 83) is mounted on the positioning ring 7, which moves synchronously with the moving frame 31. Its spray direction is precisely aimed at the cutting area of ​​the tool, mainly for immediate chip removal and cleaning of the contact area of ​​the ball bearings 81. Because this assembly is closest to the tool, it responds the fastest and can blow away the chips generated during cutting immediately, preventing chip accumulation or entanglement. The cutting fluid nozzle 35 serves as a supplementary cooling and lubrication unit, mainly used to handle areas not covered by the support chip-blowing assembly, including: auxiliary cooling at the beginning of tool entry and when the cutting depth is large, lubrication of the non-supported side of the shaft, and blind spots that the angled nozzle 83 cannot effectively cover due to chip splashing during machining. The two work together to achieve all-round cooling and chip removal. The angled nozzle 83 is responsible for rapid chip removal at the cutting point and cleaning of the ball bearings 81, while the cutting fluid nozzle 35 is responsible for large-area cooling and lubrication and replenishment of dead corners. This division of labor avoids the problem of insufficient coverage by a single nozzle and also prevents fluid waste caused by excessive overlapping spraying.

[0044] Drive unit 1 2 and drive unit 2 42 can be clamped from both ends of the motor shaft via chuck 21 (the specific choice between drive unit 1 2 or drive unit 2 42, or both, can be flexibly selected according to the specifications, length, and processing requirements of the motor shaft), forming a dual-end drive configuration. The dual-end drive can effectively reduce the torsional deformation of the slender motor shaft during the turning process, while improving the synchronization of the rotation at both ends and avoiding the accumulation of torsional stress on the shaft body caused by a single drive. For short shafts or motor shafts with good rigidity, it is also possible to choose to use drive unit 1 2 for single-end drive to simplify the operation. The first feed mechanism 3 and the second feed mechanism 4 adopt independent lead screw drives, which allows the moving frame 31 and the machine tool tailstock 41 to move independently, making it easy to adjust the tailstock position according to the length of the motor shaft. At the same time, the moving frame 31 can make precise axial feed along the bed.

[0045] The supporting chip removal assembly includes a mounting base 5 fixedly connected to the movable frame 31. A support base 6 is fixedly connected to the end of the mounting base 5. A positioning ring 7 is fixedly connected to the upper end of the support base 6. The positioning ring 7 has multiple radial cavities 71 evenly distributed along the circumference of its housing (preferably three in this embodiment, distributed at 120°). A slider 8 is slidably connected inside the radial cavity 71. The slider 8 and the inner cavity of the radial cavity 71 are elastically connected by a spring 72. An electromagnet 73 is installed on the inner side of the radial cavity 71 to control the slider 8 to reset. A ball bearing 81 is rotatably engaged at the end of the slider 8 away from the electromagnet 73. A guide channel 82 penetrating the side wall of the slider 8 is provided inside the slider 8. An oblique spray pipe 83 is connected through the end of the guide channel 82.

[0046] When rapid tool retraction or tool change is required, the electromagnet 73 is energized to pull back the slider 8, causing the ball bearing 81 to disengage from the shaft surface, thus preventing scratches on the machined surface during tool retraction. The chip-blowing support assembly is fixed to one side of the moving frame 31, allowing it to move axially with the tool, achieving follow-up support. Compared to a fixed center frame, the support point of the follow-up support is always close to the cutting area, which can suppress cutting chatter to the maximum extent and improve the rigidity during the machining of slender shafts. Spring 72 provides elastic preload, enabling the ball bearing 81 to adapt to small fluctuations in the shaft diameter (such as roundness error, uneven blank allowance), avoiding shaft bending or surface indentation caused by rigid clamping.

[0047] It should be noted that the positioning ring 7 is coaxially set with the motor shaft to be processed, ensuring that the balls 81 extending from the multiple sliders 8 can evenly contact the shaft surface, forming a self-centering support and avoiding over-positioning. The support base 6 has a transmission channel 61 inside, and the positioning ring 7 has an annular channel 62 inside. Multiple radial cavities 71 are connected through the annular channel 62. The annular channel 62 evenly distributes the external supply flow to each radial cavity 71, ensuring that the nozzle flow of each slider 8 is consistent and avoiding insufficient pressure in some nozzles due to flow deviation. The upper end of the transmission channel 61 is connected to the annular channel 62, and the lower end of the transmission channel 61 penetrates the side wall of the support base 6. A quick connector 63 is installed at the lower end of the transmission channel 61. The quick connector 63 is connected to the external supply pipeline. The quick connector 63 facilitates quick connection to the external air source or liquid source and is convenient for maintenance and replacement.

[0048] The flow channel 82 and the oblique nozzle 83 are integrated inside the slider 8, allowing fluid (compressed air or cutting fluid) to be sprayed out from near the ball 81, while simultaneously achieving the functions of cooling, chip removal and cleaning the contact area of ​​the ball 81.

[0049] It should be noted that the angle between the spray axis of the inclined nozzle 83 and the axis of the motor shaft to be processed is 30° to 60°, and its spray direction is directed towards the cutting area of ​​the tool. This allows the sprayed fluid to impact the cutting area at a certain angle, which can effectively blow away the chips without interfering with the chip flow direction of the tool due to vertical spray. At the same time, this angle range can make the fluid form a spiral sweeping effect on the shaft surface, enhancing the chip removal capability. The top of the slider 8 has an inclined groove 80 in the guide channel 82, and the top of the guide channel 82 has a guide groove 801. The function of the inclined groove 80 and the guide groove 801 is to guide the fluid to flow along the top of the slider 8 to the guide channel 82.

[0050] It should be noted that when the device is in the turning process, the electromagnet 73 is de-energized, the spring 72 pushes the slider 8 to press the ball 81 against the surface of the motor shaft to be processed, and the fluid is sprayed out through the oblique nozzle 83 at the same time; when the moving frame 31 needs to quickly retract the tool, the electromagnet 73 is energized, which overcomes the elastic force of the spring 72 to pull the slider 8 back to its original position, so that the ball 81 is removed from the surface of the motor shaft to be processed.

[0051] Furthermore, the turret tool holder 34 can be equipped with various tools (such as external turning tools, axial power tool holders, and radial power tool holders), enabling multi-process machining such as turning, milling, and drilling to be carried out in a concentrated manner, reducing tool changing time and secondary clamping errors.

[0052] In this embodiment, when the device is in the turning state, the electromagnet 73 is de-energized, the spring 72 releases its elastic force, and pushes the slider 8 to slide along the radial cavity 71 towards the axis. The ball 81 first contacts the surface of the motor shaft and maintains a certain positive pressure under the preload of the spring 72. Since the ball 81 can rotate freely, it forms rolling contact with the shaft surface, and the frictional resistance is extremely small. At the same time, the external supply pipeline inputs compressed air or cutting fluid into the transmission channel 61 through the quick connector 63. The fluid is diverted to each radial cavity 71 through the annular channel 62 and enters the slider. The flow channel 82 inside block 8 is finally ejected at high speed from the inclined nozzle 83. The jet fluid impacts the cutting area of ​​the tool at an angle of 30° to 60°, blowing away the chips generated during turning in time, while carrying away the cutting heat, reducing the temperature of the tool and workpiece, extending tool life and reducing thermal deformation, and cleaning the contact area between the ball 81 and the shaft, washing away any tiny chips or dust that may fall into this area. Since the chip blowing assembly is fixed on the moving frame 31, its support point moves synchronously with the tool, always providing radial support near the cutting point, which significantly improves the dynamic rigidity of the machining system.

[0053] In particular, since the motor shaft is in a continuous rotating state during the turning process, the relative position between the shaft surface and the ball 81 is constantly changing. The fluid can repeatedly flush the entire circumferential contact zone from different angles. This dynamic cleaning effect is far superior to that of a static state. The rotating shaft surface will throw the chips away from the contact area, and at the same time, the fluid impact can more evenly cover the entire movement trajectory of the ball 81. Therefore, this device can effectively prevent chips from embedding between the ball 81 and the shaft surface, avoid causing scratches on the shaft surface or jamming of the ball 81, and significantly improve the long-term reliability of the support system.

[0054] When the moving frame 31 needs to quickly retract the tool (such as to complete a machining cycle, change tools, or measure workpieces), the control system energizes the electromagnet 73. The electromagnet 73 generates a magnetic field, which overcomes the elastic force of the spring 72 and pulls the slider 8 back to the inner side of the radial cavity 71. The ball 81 disengages from the surface of the motor shaft, forming a certain gap. At this time, the moving frame 31 can drive the entire support chip blowing assembly to quickly retract along the axial direction without causing any scratches or friction marks on the machined surface. Optionally, a small amount of fluid can be sprayed out during the tool retraction process to clean residual chips on the shaft surface.

[0055] It should be noted that the external supply line can be connected to compressed air or cutting fluid, and air / liquid switching can also be achieved through a three-way valve. Compressed air is used in the roughing stage to focus on chip removal and vibration stress relief (in conjunction with pneumatic vibration components), while cutting fluid is used in the finishing stage to focus on cooling and lubrication to improve surface finish. A small amount of cutting oil can also be mixed into the compressed air to balance cooling, lubrication and environmental protection.

[0056] In this embodiment, the chip removal support assembly moves synchronously with the moving frame 31, and the support point is always close to the cutting area, providing effective radial stiffness compensation for the slender motor shaft, which can significantly reduce tool deflection and chatter, and improve machining accuracy. Spring 72 provides elastic preload, allowing the ball bearing 81 to adapt to small changes in shaft diameter, and will not be forcibly pressed due to uneven blank allowance or shaft bending, thus avoiding the introduction of new deformation. When the tool retracts, the electromagnet 73 is energized to pull back the slider 8, causing the ball bearing 81 to detach from the shaft surface, avoiding scratches during tool retraction, which is especially suitable for protecting the already machined surface. By integrating the fluid jet function into the slider 8, which is synchronized with the support action, there is no need to add an additional nozzle support, resulting in a compact structure and high chip removal efficiency as the jet direction is directed towards the cutting area. Compressed air, cutting fluid, or aerosol can be introduced to meet the needs of different machining stages.

[0057] Example 2, refer to Figures 8-12 The pneumatic vibration assembly includes a mounting cavity 84 and a movable cavity 90. The mounting cavity 84 is located beside and connected to the guide channel 82. A rotating wheel assembly 85 is rotatably connected inside the mounting cavity 84. A movable rod 9 is slidably connected inside the movable cavity 90. One end of the movable rod 9 passes through the side wall of the mounting cavity 84 and extends into the mounting cavity 84, while the other end passes through the outer wall of the slider 8 and extends out of the slider 8. A limiting plate 91 is fixedly connected to the movable rod 9 inside the movable cavity 90. The limiting plate 91 is elastically connected to the inner wall of the movable cavity 90 by a spring 94. A dome 93 is provided at the end of the movable rod 9 inside the mounting cavity 84, and a connecting block 92 is fixedly connected to the end of the movable rod 9 outside the slider 8.

[0058] With the above setup, the pneumatic vibration component is fully integrated inside the slider 8 without increasing the external size of the device. It utilizes the fluid kinetic energy in the existing flow channel 82 as a power source, eliminating the need for an additional motor or vibrator.

[0059] It should be noted that the movable cavity 90 is inclined, and the mounting cavity 84 is parallel to the movable cavity 90. This arrangement makes the movement direction of the movable rod 9 form a certain angle with the radial direction of the slider 8, thereby generating a composite vibration force (with both radial and tangential components) at the contact point between the ball 81 and the shaft, enhancing the stress relief effect. When the second spring 94 is in the initial state, the limiting plate 91 abuts against the end of the movable cavity 90, and the side wall of the connecting block 92 abuts against the outer side wall of the slider 8, ensuring that the vibration force can be effectively generated when the second spring 94 is reset.

[0060] Furthermore, the rotating wheel assembly 85 is alternately equipped with long arc plates 851 and short arc plates 852. When the fluid passes through the guide channel 82, the fluid drives the rotating wheel assembly 85 to rotate. When the spring 94 is in its initial state, the dome 93 is positioned between the movement trajectories of the long arc plates 851 and the short arc plates 852, allowing the end of the long arc plate 851 to contact the dome 93, while the end of the short arc plate 852 does not contact the dome 93. This ensures that for each rotation of the rotating wheel assembly 85, each long arc plate 851 contacts the dome 93 only once, while the short arc plate 852 does not contact it. Thus, the reciprocating motion frequency generated by the movable rod 9 is equal to the rotational speed of the rotating wheel assembly 85 multiplied by the long arc plate 851. The number of blades facilitates the control of vibration frequency through fluid flow. When the long arc plate 851 pushes the dome 93 to move the movable rod 9 outward, the spring 94 will then push the movable rod 9 back to its original position, forming a complete reciprocating vibration cycle. The ends of the long arc plate 851 and the short arc plate 852 are both arc-shaped, and the contact with the dome 93 is a smooth rolling contact, reducing wear and impact noise. The wheel assembly 85 converts fluid kinetic energy into rotational mechanical energy, and then through the periodic contact between the dome 93 and the long arc plate 851, the rotational motion is converted into the axial reciprocating motion of the movable rod 9. Finally, the vibration is transmitted to the slider 8 and the ball 81 through the limiting plate 91 and the connecting block 92.

[0061] In this embodiment, when compressed air (or cutting fluid) is introduced into the external supply pipeline, the fluid enters each radial cavity 71 through the transmission channel 61 and the annular channel 62, and then flows into the guide channel 82 in the slider 8. When flowing through the mounting cavity 84, the fluid impacts the long arc plate 851 and the short arc plate 852 on the rotating wheel assembly 85, generating tangential force and driving the rotating wheel assembly 85 to rotate around its axis.

[0062] The rotating wheel assembly 85 is alternately equipped with long arc plates 851 and short arc plates 852. The end of the long arc plate 851 can contact the dome 93, while the end of the short arc plate 852 does not contact the dome 93. Therefore, each long arc plate 851 contacts the dome 93 only once per revolution of the rotating wheel. When the long arc plate 851 pushes the dome 93, the movable rod 9 extends outward against the elastic force of the second spring 94. After the long arc plate 851 passes the dome 93, the second spring 94 releases energy and pushes the limit plate 91 and the movable rod 9 to reset. This cycle continues, and the movable rod 9 generates periodic axial reciprocating motion. The reciprocating motion frequency of the movable rod 9 is equal to the rotation speed of the rotating wheel assembly 85 multiplied by the number of blades of the long arc plate 851. The vibration frequency can be steplessly adjusted by adjusting the fluid pressure or flow rate.

[0063] Using the tool feed direction as a reference, define the coordinate system as follows: the machine tool spindle axis is the Y-axis (horizontal), the tool feed direction is the X-axis (horizontal, perpendicular to the Z-axis), and the vertical direction is the Z-axis. When the mounting cavity 84 is perpendicular to the tool feed direction (e.g.) Figure 12As shown, at this time, the mounting cavity 84 is in the ZOY plane), and the resultant force of the vibration generated by the limiting plate 91 and the connecting block 92 passes through the axis of the motor shaft to be processed; as described in Embodiment 2, the rotating wheel assembly 85 in the pneumatic vibration assembly rotates under fluid drive, and the long arc plate 851 periodically pushes the dome 93, causing the movable rod 9 to produce axial reciprocating motion. When the movable rod 9 extends outward and then returns to its original position, it generates two forces in different directions:

[0064] Point of action A (connecting block 92): Connecting block 92 is in parallel contact with the outer wall of slider 8. When the movable rod 9 extends outward, connecting block 92 moves together with the movable rod 9. When the movable rod 9 returns to its original position, connecting block 92 applies a horizontal thrust (denoted as F1) to the outer wall of slider 8.

[0065] Point of application B (limiting plate 91): When the movable rod 9 extends outward, the limiting plate 91 compresses the second spring 94; when the long arc plate 851 rotates past the dome 93, the second spring 94 releases energy, pushing the limiting plate 91 and the movable rod 9 to reset. During this process, the limiting plate 91 applies a force (denoted as F2) along the axis of the movable rod 9 to the end of the movable cavity 90. Since the movable cavity 90 is inclined, the direction of this force is the inclined direction (the angle with the horizontal direction is θ, where θ is the inclination angle of the movable cavity 90, which is 30° to 60°). Therefore, within a complete vibration cycle, the slider 8 is subjected to two forces in different directions and at different times: the horizontal thrust from the connecting block 92 and the inclined thrust from the limiting plate 91. The two forces act together on the slider 8 and are transmitted to the motor shaft surface in the form of pulsating pressure through the ball 81. The direction of the resultant force F3 is determined by the ratio of F1 to F2, and can be controlled by adjusting the fluid pressure or selecting springs 94 with different stiffnesses.

[0066] When the mounting cavity 84 is perpendicular to the tool feed direction (located in the ZOY plane), by designing the geometric matching between the circumferential position of the slider 8 and the tilt angle θ of the movable cavity 90, and by presetting the amplitude ratio of F1 and F2, the resultant force direction can be made to point towards the axis along the radial direction of the slider 8. At this time, the resultant force F3 itself is tilted (the angle between its direction and the horizontal direction is equal to the radial angle β of the slider 8), but since its line of action passes through the axis, the ball 81 applies alternating pressure in the radial direction to the motor shaft. This pressure wave generates periodic compression and tensile strain on the shaft surface and subsurface, causing microscopic plastic relaxation of the residual tensile stress in turning, while changing the dynamic stiffness of the cutting system and destroying the formation conditions of self-excited chatter. This mode is suitable for chatter suppression and uniform stress elimination in the finishing stage.

[0067] Similarly, when the mounting cavity 84 is parallel to the tool feed direction (not shown in the figure, at which time the mounting cavity 84 is in the ZOX plane), the resultant force of the vibration generated by the limiting plate 91 and the connecting block 92 does not pass through the axis of the motor shaft to be processed, and will generate alternating torque, introducing bending stress in the shaft section. Since the motor shaft is in a rotating state, the direction of this bending stress changes periodically with the rotation, forming a full-circumferential alternating stress field, which can activate the dislocation movement of multiple slip systems inside the material and promote the release of deep (0.5~2mm) residual stress. This mode is more effective in eliminating large residual stress after rough machining, and is particularly suitable for eliminating deep residual stress introduced by forging, rolling or rough turning.

[0068] By changing the installation orientation of the mounting cavity 84 and related processes, the resultant force of vibration can be adjusted to whether it passes through the shaft center. When the resultant force passes through the shaft center (the direction of the resultant force itself is inclined, but its line of action passes through the shaft center), it mainly generates radial pulsating pressure, which is suitable for chatter suppression and uniform stress elimination in the finishing stage. When the resultant force does not pass through the shaft center (generating eccentric torque), in addition to the radial component, the vibration will introduce alternating bending stress in the shaft section, which helps to activate the multi-slip system inside the material and has a better effect on eliminating large residual stress after roughing. Users can choose to install the pneumatic vibration assembly in the slider 8 at different circumferential positions, or install multiple vibration assemblies in different directions in one positioning ring 7, depending on the machining stage and the material of the motor shaft. It should be noted that no matter how the vibration assembly is configured, the outlet direction of the oblique nozzle 83 always faces the turning area to ensure that the chip removal and cooling functions are not affected. Through the above configuration, composite stress field loading can be achieved, further improving machining quality and efficiency.

[0069] The pneumatic vibration assembly is driven entirely by the fluid (compressed air or cutting fluid) already present in the machining device, requiring no additional exciter, power supply, or controller, thus achieving active vibration excitation with zero additional energy consumption. The vibration frequency can be steplessly changed by adjusting the fluid pressure or flow rate without replacing any parts. By installing multiple pneumatic vibration assemblies in different directions in the positioning ring 7, radial pressure and eccentric torque can be applied simultaneously to achieve composite stress field loading, further improving the uniformity and depth of stress relief. Compressed air, cutting fluid, or aerosol can be introduced, making it suitable for dry, wet, and semi-dry machining. It can be installed on positioning rings 7 of different diameters to accommodate motor shafts of different specifications. It can be applied to various materials such as carbon steel, alloy steel, and stainless steel.

[0070] The control method of this invention is automatic control through a controller. The control circuit of the controller can be implemented by simple programming by those skilled in the art. The power supply is also common knowledge in the field. Since this invention is mainly used to protect mechanical devices, the control method and circuit connection will not be explained in detail. The specific model and specifications of the relevant electrical components need to be selected and determined according to the actual specifications of the device. The specific selection and calculation method adopts the existing technology in the field, so it will not be described in detail.

[0071] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the invention by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the invention should be included within the scope of protection of the invention.

Claims

1. A turning apparatus for a motor shaft, comprising a machine bed (1) and a movable frame (31) mounted on the machine bed (1), characterized in that, Also includes: The chip blowing assembly is located on one side of the movable frame (31) and is used to provide follow-up support for the motor shaft to be processed, while also blowing away machining chips. The supporting chip blowing assembly includes a mounting base (5) fixedly connected to a movable frame (31), a support base (6) fixedly connected to the end of the mounting base (5), a positioning ring (7) fixedly connected to the upper end of the support base (6), and a plurality of radial cavities (71) evenly distributed along the circumference of the positioning ring (7); a slider (8) is slidably connected inside the radial cavity (71), and the slider (8) is elastically connected to the inner cavity of the radial cavity (71) by a spring (72); an electromagnet (73) for controlling the slider (8) to reset is installed on the inner side of the radial cavity (71), and a ball bearing (81) is rotatably engaged at the end of the slider (8) away from the electromagnet (73); a guide channel (82) penetrating the side wall of the slider (8) is provided inside the slider (8), and an oblique spray pipe (83) is connected through the end of the guide channel (82); A pneumatic vibration assembly is mounted on a support chip blowing assembly to eliminate stress generated during the cutting of the surface of the motor shaft to be processed. The pneumatic vibration assembly includes a mounting cavity (84) and a movable cavity (90). The mounting cavity (84) is located beside and communicates with the guide channel (82). A rotating wheel assembly (85) is rotatably connected inside the mounting cavity (84). A movable rod (9) is slidably connected inside the movable cavity (90). One end of the movable rod (9) passes through the cavity of the mounting cavity (84). The side wall of the body extends into the placement cavity (84), and the other end passes through the outer side wall of the slider (8) and extends out of the slider (8); a limiting plate (91) is fixedly connected to the movable rod (9) located in the movable cavity (90), and the limiting plate (91) and the inner wall of the movable cavity (90) are elastically connected by a spring (94); the end of the movable rod (9) located in the placement cavity (84) is provided with a dome (93), and the end of the movable rod (9) located outside the slider (8) is fixedly connected with a connecting block (92).

2. The turning apparatus for a motor shaft according to claim 1, characterized in that, The machine tool bed (1) is provided with a first feed mechanism (3) and a second feed mechanism (4) on its side. The machine tool bed (1) is also slidably connected to a machine tool tailstock (41). A drive device (2) is installed on the machine tool bed (1), and a drive device (42) is installed on the machine tool tailstock (41). The output ends of the drive device (2) and the drive device (42) are both provided with chucks (21). The output ends of the first feed mechanism (3) and the second feed mechanism (4) are both connected to lead screws. The lead screw on the mechanism (3) is threadedly connected to the moving frame (31), and the lead screw on the second feed mechanism (4) is threadedly connected to the tailstock (41) of the machine tool; a tool holder base (32) is slidably connected on the moving frame (31), a tool rotating mechanism (33) is installed on the tool holder base (32), a turret tool holder (34) is provided at the output end of the tool rotating mechanism (33), and a cutting fluid spray pipe (35) is inserted into one side of the tool holder base (32); a machine tool shell (10) is provided on the outside of the machine tool bed (1).

3. The turning apparatus for a motor shaft according to claim 1, characterized in that, The positioning ring (7) is coaxially arranged with the motor shaft to be processed. The support base (6) has a transmission channel (61) inside. The positioning ring (7) has an annular channel (62) inside. The multiple radial cavities (71) are connected through the annular channel (62). The upper end of the transmission channel (61) is connected to the annular channel (62). The lower end of the transmission channel (61) penetrates the side wall of the support base (6). A quick connector (63) is installed at the lower end of the transmission channel (61). The quick connector (63) is connected to the external power supply pipeline.

4. The turning apparatus for a motor shaft according to claim 1, characterized in that, The angle between the spray axis of the oblique nozzle (83) and the axis of the motor shaft to be processed is 30° to 60°, and its spray direction is directed towards the cutting area of ​​the tool; the top of the slider (8) is provided with an oblique groove (80) for the guide channel (82), and the top of the guide channel (82) is provided with a guide groove (801).

5. The turning apparatus for a motor shaft according to claim 1, characterized in that, When the device is in the turning process, the electromagnet (73) is de-energized, and the spring (72) pushes the slider (8) to press the ball (81) against the surface of the motor shaft to be processed. At the same time, the fluid is sprayed out through the oblique nozzle (83). When the moving frame (31) needs to quickly retract the tool, the electromagnet (73) is energized, and the spring force of the spring (72) is overcome to pull the slider (8) back to its original position, so that the ball (81) is separated from the surface of the motor shaft to be processed.

6. The turning apparatus for a motor shaft according to claim 1, characterized in that, The movable cavity (90) is inclined, and the placement cavity (84) is parallel to the movable cavity (90); when the second spring (94) is in the initial state, the limiting plate (91) abuts against the end of the movable cavity (90), and the side wall of the connecting block (92) abuts against the outer side wall of the slider (8); With reference to the feed direction of the tool, when the axis of the mounting cavity (84) is perpendicular to the feed direction of the tool, the resultant force of the vibration generated by the limiting plate (91) and the connecting block (92) passes through the axis of the motor shaft to be processed; when the axis of the mounting cavity (84) is parallel to the feed direction of the tool, the resultant force of the vibration generated by the limiting plate (91) and the connecting block (92) does not pass through the axis of the motor shaft to be processed.

7. The turning apparatus for a motor shaft according to claim 1, characterized in that, The rotating wheel assembly (85) is alternately provided with long arc plate (851) and short arc plate (852), and the ends of the long arc plate (851) and the short arc plate (852) are both arc-shaped.

8. The turning apparatus for a motor shaft according to claim 7, characterized in that, When the fluid passes through the guide channel (82), the fluid drives the rotating wheel assembly (85) to rotate; when the second spring (94) is in the initial state, the dome (93) is between the movement trajectories of the long arc plate (851) and the short arc plate (852), so that the end of the long arc plate (851) can contact the dome (93), while the end of the short arc plate (852) does not contact the dome (93).

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