Motor shaft core precision straightening and residual stress relieving device

Abstract

The utility model discloses a motor shaft core precision straightening and residual stress elimination device belongs to motor manufacturing technical field, including support, straightening and eliminating mechanism and PLC controller, and straightening and eliminating mechanism includes laser displacement sensor, servo electric cylinder, spherical anvil and high frequency induction heating coil, and PLC controller is electric connection with laser displacement sensor, servo electric cylinder and high frequency induction heating coil respectively, and the detection signal of PLC controller according to laser displacement sensor controls servo electric cylinder to drive spherical anvil to execute straightening action, and immediately controls high frequency induction heating coil to heat straightening area after straightening action is completed. The utility model integrates straightening and stress relief procedure as a whole, solved the post -deformation problem of residual stress after straightening, realized on -line stress relief, improved the long -term dimensional stability of shaft core and production efficiency significantly.

Description

Technical Field

[0001] This utility model relates to the field of motor manufacturing technology, and in particular to a device for precision straightening and residual stress relief of motor shaft core. Background Technology

[0002] The motor shaft is the core transmission component of the motor. Its straightness and coaxiality accuracy directly affect the smoothness of motor operation, noise, vibration and overall service life. During heat treatment, machining and assembly manufacturing, the motor shaft may bend and deform due to the release of internal stress or the action of external force. Therefore, the straightening process is a key link to ensure the quality of the shaft.

[0003] Currently, the commonly used straightening method is the mechanical reverse bending pressing method. This method uses testing equipment to find the maximum bending point of the shaft core and then applies a reverse force to cause plastic deformation in the bent area, thereby restoring its straightness. However, this simple mechanical straightening method has a deep-seated technical defect: reverse bending straightening is essentially a forced cold plastic deformation process. While it straightens the shaft core macroscopically, it inevitably introduces new and complex residual stresses into the metal material in the straightening area.

[0004] This residual stress is in an unstable metastable state. Although the shaft is straight immediately after straightening, it will gradually release during subsequent storage and transportation, or when affected by temperature changes and vibration loads during actual motor operation. This causes the shaft to deform slightly again, a phenomenon known as "post-springback." This springback reduces the accuracy of the shaft, which has already met the standards, and seriously affects the long-term reliability and performance stability of the motor. To solve the problem of residual stress, traditional processes usually require an additional independent overall heat treatment process after mechanical straightening, such as stress relief annealing, to eliminate the internal stress of the shaft. However, treating straightening and stress relief as two separate processes not only makes the entire production process lengthy and complex, requiring multiple transfers and clamping, which significantly reduces production efficiency, but also makes it difficult to achieve full-process automated control, increasing production costs and the risk of introducing secondary errors.

[0005] Therefore, this utility model proposes a device for precision straightening of motor shaft core and elimination of residual stress to overcome the shortcomings of the prior art. Utility Model Content

[0006] In view of the problems in the existing technology of a precision straightening and residual stress relief device for motor shafts, the residual stress generated after straightening will cause the shaft to spring back later and affect the dimensional stability. In addition, the straightening and stress relief processes are separated, the process is lengthy and complicated, and the degree of automation is low. The present invention aims to provide a precision straightening and residual stress relief device for motor shafts with an improved structure that can effectively solve the above problems.

[0007] This utility model provides a device for precision straightening and residual stress relief of motor shaft core, comprising: a bracket; a straightening and stress relief mechanism mounted on the bracket; and a PLC controller; The correction mechanism includes a servo motor and a pin for clamping and rotating the motor shaft; the correction mechanism also includes a laser displacement sensor for detecting the radial runout of the motor shaft. The straightening mechanism also includes a servo electric cylinder for applying reverse bending straightening force and a spherical indenter, as well as a high-frequency induction heating coil disposed near the working area of ​​the spherical indenter; Furthermore, the PLC controller is electrically connected to the laser displacement sensor, the servo electric cylinder, and the high-frequency induction heating coil, respectively. The PLC controller is used to control the servo electric cylinder to perform a straightening action according to the detection signal of the laser displacement sensor, and immediately control the high-frequency induction heating coil to heat the straightened area after the servo electric cylinder completes the action.

[0008] Preferably, the device further includes at least two shaft core placement platforms disposed inside the bracket, and an adjustment mechanism for adjusting the distance between the at least two shaft core placement platforms; the adjustment mechanism includes a bidirectional lead screw rotatably disposed on the bracket, and at least two sliders, each slider being threadedly engaged with both ends of the bidirectional lead screw, and the shaft core placement platforms being fixed to the sliders.

[0009] Preferably, the adjusting mechanism further includes a rotating rod, a driving bevel gear, and a transmission bevel gear. The rotating rod is connected to the driving bevel gear, the driving bevel gear meshes with the transmission bevel gear, and the transmission bevel gear is coaxially connected to the bidirectional lead screw for driving the bidirectional lead screw to rotate.

[0010] Preferably, the correction mechanism further includes a sliding base and an electric telescopic rod. The servo motor is mounted on the sliding base, and the electric telescopic rod is used to push the sliding base to move so that the ejector pin clamps or releases the motor shaft.

[0011] Preferably, the correction mechanism further includes a hydraulic lifting rod, which is mounted on the sliding base and moves together with the sliding base.

[0012] Preferably, the device further includes a second slider and a second electric telescopic rod. The servo electric cylinder, the spherical pressure head, and the high-frequency induction heating coil are all mounted on the second slider. The second electric telescopic rod is used to drive the second slider to move axially along the motor shaft to adjust the straightening position.

[0013] Preferably, the correction mechanism further includes a force sensor, which is disposed between the servo electric cylinder and the spherical pressure head and electrically connected to the PLC controller for monitoring the bending force applied by the spherical pressure head.

[0014] This utility model has the following beneficial effects: 1. This utility model, by setting up a straightening mechanism, after the spherical pressure head completes the precision reverse bending and straightening action, the high-frequency induction heating coil immediately performs short-term low-temperature induction heating on the local micro-area that has just undergone plastic deformation and rapidly self-cools it. This solves the problem of residual stress generated by straightening in the prior art causing the shaft core to deform later. It achieves the technical effect of eliminating residual stress online and fundamentally improving the long-term dimensional stability of the shaft core and the reliability of the motor.

[0015] 2. This utility model integrates the straightening and stress relief processes into one unit by using a PLC controller to coordinate the control of a laser displacement sensor, a servo electric cylinder, and a high-frequency induction heating coil. At the same time, it achieves adaptive adjustment of shaft cores of different lengths and bending positions through an adjustment mechanism and an electric telescopic rod component. This solves the problems of process separation, cumbersome process, low degree of automation, and difficulty in adapting to shaft cores of different specifications in the prior art, and achieves the technical effect of improving production efficiency and realizing highly automated and flexible production. Attached Figure Description

[0016] Figure 1 This is a perspective view of a device for precision straightening and residual stress relief of a motor shaft according to the present invention. Figure 2 This is a front view of a device for precision straightening and residual stress relief of a motor shaft according to the present invention. Figure 3 This is an exploded view of the straightening mechanism of a precision straightening and residual stress relief device for motor shaft core proposed in this utility model; Figure 4 This is a schematic diagram of the adjustment mechanism of a precision straightening and residual stress relief device for motor shaft core proposed in this utility model.

[0017] Explanation of reference numerals in the attached figures: 1. Bracket; 2. Correction mechanism; 201. Sliding base; 202. Electric telescopic rod one; 203. Hydraulic lifting rod; 204. Servo motor; 205. Ejector pin; 206. Servo electric cylinder; 207. Spherical pressure head; 208. High-frequency induction heating coil; 209. Force sensor; 210. Laser displacement sensor; 211. PLC controller; 3. Adjustment mechanism; 301. Slider one; 302. Bidirectional lead screw; 303. Transmission bevel gear; 304. Rotating rod; 305. Drive bevel gear; 4. Shaft core placement platform; 5. Slider two; 6. Electric telescopic rod two. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions in the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this utility model, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are within the scope of protection of this utility model.

[0019] Example: Please refer to Figure 1 and Figure 2 A precision straightening and residual stress relief device for motor shafts includes a bracket 1, which serves as the mounting base for the entire device. A straightening and stress relief mechanism 2 is mounted on the bracket 1. The device also includes a PLC controller 211 for coordinated control, and at least two shaft placement platforms 4 located on the inner bottom of the bracket 1. These platforms 4 support the motor shaft before clamping by a pin 205. The device further includes an adjustment mechanism 3 mounted on the bottom of the bracket 1, used to adjust the spacing between the at least two shaft placement platforms 4 to accommodate motor shafts of different lengths. Figure 4 As shown, the adjusting mechanism 3 includes a rotating rod 304, a driving bevel gear 305, and a transmission bevel gear 303. The rotating rod 304 passes through the side wall of the bracket 1 and is connected to the driving bevel gear 305. The driving bevel gear 305 meshes with the transmission bevel gear 303. The adjusting mechanism 3 also includes a bidirectional lead screw 302. The transmission bevel gear 303 is coaxially fixedly connected to the bidirectional lead screw 302 and is used to drive the bidirectional lead screw 302 to rotate. The bidirectional lead screw 302 is rotatably mounted on the bracket 1. The adjusting mechanism 3 also includes at least two sliders 301. The sliders 301 are threaded to both ends of the bidirectional lead screw 302. The shaft core placement platform 4 is fixedly connected to the sliders 301. The sliders 301 slide along the inner wall of the bracket 1. Figure 3 As shown, the correction mechanism 2 includes a servo motor 204 and a pin 205 for clamping and rotating the motor shaft. The correction mechanism 2 also includes a sliding base 201 and an electric telescopic rod 202. The servo motor 204 is mounted on the sliding base 201. The correction mechanism 2 also includes a hydraulic lifting rod 203, which is mounted on the sliding base 201 and located below the servo motor 204 and moves with the sliding base 201. One end of the electric telescopic rod 202 is fixed to the bracket 1, and the other end pushes the sliding base 201 to move so that the pin 205 clamps or releases the motor shaft.

[0020] The correction mechanism 2 also includes a laser displacement sensor 210 for detecting the radial runout of the motor shaft. The laser displacement sensor 210 is fixedly installed at an appropriate position above the bracket 1 and aligned with the motor shaft held by the ejector pin 205. The device also includes a second slider 5 and an electric telescopic rod 6. The electric telescopic rod 6 is fixed to the top crossbeam of the bracket 1, and the second slider 5 is slidably connected to the top crossbeam of the bracket 1. The telescopic end of the electric telescopic rod 6 drives the second slider 5 to reciprocate along the axial direction of the motor shaft. The correction mechanism 2 also includes a servo electric cylinder 206, which is vertically installed on the second slider 5 and moves with the second slider 5. The bottom end of the servo electric cylinder 206 is connected to a spherical pressure head 207. The correction mechanism 2 also includes a force sensor 209, which is disposed between the servo electric cylinder 206 and the spherical pressure head 207 to monitor the bending force applied by the spherical pressure head 207. The correction mechanism 2 also includes a high-frequency induction heating element. The heating coil 208, a high-frequency induction heating coil, is located near the working area of ​​the spherical indenter 207 and is fixed to the slider 5, moving together with it. The PLC controller 211 is electrically connected to the servo motor 204, the electric telescopic rod 202, the laser displacement sensor 210, the servo electric cylinder 206, the high-frequency induction heating coil 208, the force sensor 209, and the electric telescopic rod 6. The PLC controller 211 is used to control the servo electric cylinder 206 to perform straightening action according to the detection signal of the laser displacement sensor 210, and immediately control the high-frequency induction heating coil 208 to heat the straightening area after the servo electric cylinder 206 completes the action. The PLC controller 211 is also used to receive the monitoring signal of the force sensor 209. The PLC controller 211 also controls the electric telescopic rod 6 to drive the slider 5 to move, so as to adjust the axial position of the spherical indenter 207 and the high-frequency induction heating coil 208.

[0021] As a preferred embodiment, to accommodate motor shafts of different lengths, please refer to... Figure 1 and Figure 4 The device also includes at least two shaft core placement platforms 4 disposed inside the bracket 1. The shaft core placement platforms 4 are used to support the motor shaft core before the ejector pin 205 clamps. The device also includes an adjustment mechanism 3, which is used to adjust the distance between the at least two shaft core placement platforms 4. For further definition of the adjustment mechanism 3, please refer to [reference needed]. Figure 4 The adjusting mechanism 3 includes a bidirectional lead screw 302, which is rotatably mounted on the bracket 1. The adjusting mechanism 3 also includes at least two sliders 301, which are threadedly engaged with both ends of the bidirectional lead screw 302. The shaft core placement platform 4 is fixedly connected to each slider 301. For further definition of the adjusting mechanism 3, please refer to [reference needed]. Figure 4To facilitate driving the bidirectional lead screw 302, the adjusting mechanism 3 also includes a rotating rod 304, a driving bevel gear 305, and a transmission bevel gear 303. The rotating rod 304 is connected to the driving bevel gear 305, the driving bevel gear 305 meshes with the transmission bevel gear 303, and the transmission bevel gear 303 is coaxially connected to the bidirectional lead screw 302. As a preferred embodiment, to achieve automatic clamping of the motor shaft, please refer to... Figure 3 The correction mechanism 2 also includes a sliding base 201 and an electric telescopic rod 202. A servo motor 204 is mounted on the sliding base 201. The electric telescopic rod 202 is used to push the sliding base 201 to move, thereby causing the ejector pin 205 to clamp or release the motor shaft. As a supplement to the clamping mechanism, please refer to... Figure 3 The straightening mechanism 2 also includes a hydraulic lifting rod 203, which is mounted on the sliding base 201 and moves together with the sliding base 201. As a preferred embodiment, in order to straighten different positions along the axial direction of the motor shaft, please refer to... Figure 1 and Figure 3 The device also includes a second slider 5 and a second electric telescopic rod 6. A servo electric cylinder 206, a spherical pressure head 207, and a high-frequency induction heating coil 208 are all mounted on the second slider 5. The second electric telescopic rod 6 is fixed to the top of the bracket 1 and is used to drive the second slider 5 to move axially along the motor shaft. As a preferred embodiment, to achieve precise monitoring of the straightening pressure, please refer to... Figure 3 The correction mechanism 2 also includes a force sensor 209, which is located between the servo electric cylinder 206 and the spherical pressure head 207 and is electrically connected to the PLC controller 211.

[0022] Working principle: When using a precision straightening and residual stress relief device for motor shafts, the motor shaft is first placed on the shaft placement platform 4 inside the bracket 1. The straightening and stress relief mechanism 2 then functions, and the PLC controller 211 controls the electric telescopic rod 202 to extend and push the sliding base 201, causing the hydraulic lifting rod 203 and the servo motor 204 above to slide inward. When the electric telescopic rod 202 pushes the sliding base 201 into place, the ejector pins 205 clamp the two ends of the motor shaft from the left and right sides. At this time, the servo motor 204 starts, and its output end rotates. The ejector pin 205 rotates, causing the motor shaft to rotate at a constant speed. The laser displacement sensor 210 monitors the radial runout of the shaft during rotation and locates the maximum bending point and its phase. After this, the servo electric cylinder 206, based on the information transmitted from the laser displacement sensor 210 to the PLC controller 211, extends downwards from its bottom end when the shaft reaches the maximum bending point, driving the spherical pressure head 207 to apply a precise, programmable bending amount to the motor shaft for high-precision reverse bending straightening. During this process... After the spherical indenter 207 completes one bending and straightening action, the high-frequency induction heating coil 208 immediately performs short-term, low-temperature induction heating on the localized micro-area that has just undergone plastic deformation, followed by rapid self-cooling. This effectively eliminates the micro-stress in the area without changing the overall metallographic structure and hardness of the shaft core. The force sensor 209 is used to monitor the actual bending force as an auxiliary monitoring parameter of the process. When it is necessary to adjust the downward position of the spherical indenter 207, the electric telescopic rod 26 pushes or pulls back the slider 25, which in turn moves the servo electric cylinder 206 to the left or right. The spherical pressure head 207 can be precisely adjusted to press down. The PLC controller 211 receives the measurement data from the laser displacement sensor 210 and the force sensor 209, and controls the servo motor 204, servo electric cylinder 206 and high-frequency induction heating coil 208 to work together. This realizes the merging of the separate straightening and stress relief processes into one online process, solves the problem of later deformation caused by residual stress, improves the long-term stability of the shaft core and the reliability of the motor, and can quickly adapt to shaft cores of different specifications and materials by modifying the program parameters, thereby improving production efficiency. Furthermore, when it is necessary to adjust the distance between the two shaft core placement platforms 4 to accommodate motor shaft cores of different lengths, rotating the rotating rod 304 drives the drive bevel gear 305 to rotate. Since the drive bevel gear 305 is meshed with the transmission bevel gear 303, when the drive bevel gear 305 rotates, it will drive the transmission bevel gear 303 and the double-acting screw 302 to rotate together. When the double-acting screw 302 rotates, the sliders 301 on both sides of its outer wall will slide towards each other along the inner wall of the bracket 1. When the sliders 301 move, they will drive the shaft core placement platform 4 to slide on the inner bottom of the bracket 1, thereby completing the adjustment of the distance between the two shaft core placement platforms 4. Through the cooperation of the various components in the adjustment mechanism 3, the device can adapt to motor shaft cores of different lengths.

Claims

1. A device for precision straightening and residual stress relief of motor shaft core, comprising: Support (1); The correction mechanism (2) is mounted on the bracket (1). The correction mechanism (2) includes a servo motor (204) for clamping and driving the motor shaft to rotate and a pin (205). The correction mechanism (2) also includes a laser displacement sensor (210) for detecting the radial runout of the motor shaft. PLC controller (211); Its features are, The straightening mechanism (2) further includes: a servo electric cylinder (206) for applying the reverse bending straightening force and a spherical pressure head (207). And a high-frequency induction heating coil (208) disposed near the working area of ​​the spherical pressure head (207); The PLC controller (211) is electrically connected to the laser displacement sensor (210), the servo electric cylinder (206), and the high-frequency induction heating coil (208) respectively. The PLC controller (211) is used to control the servo electric cylinder (206) to perform a straightening action according to the detection signal of the laser displacement sensor (210), and immediately control the high-frequency induction heating coil (208) to heat the straightening area after the servo electric cylinder (206) completes the action.

2. The device for precision straightening and residual stress relief of motor shaft core according to claim 1, characterized in that, The device also includes a second slider (5) and a second electric telescopic rod (6). The servo electric cylinder (206), the spherical pressure head (207) and the high-frequency induction heating coil (208) are all mounted on the second slider (5). The second electric telescopic rod (6) is used to drive the second slider (5) to move axially along the motor shaft to adjust the straightening position.

3. The device for precision straightening and residual stress relief of a motor shaft core according to claim 1, characterized in that, The correction mechanism (2) also includes a force sensor (209), which is located between the servo electric cylinder (206) and the spherical pressure head (207) and is electrically connected to the PLC controller (211) to monitor the bending force applied by the spherical pressure head (207).

4. The device for precision straightening and residual stress relief of a motor shaft core according to claim 1, characterized in that, The correction mechanism (2) further includes a sliding base (201) and an electric telescopic rod (202). The servo motor (204) is mounted on the sliding base (201). The electric telescopic rod (202) is used to push the sliding base (201) to move so that the ejector pin (205) clamps or releases the motor shaft.

5. The device for precision straightening and residual stress relief of a motor shaft core according to claim 1, characterized in that, The device further includes: At least two shaft core placement platforms (4) are provided inside the bracket (1) to support the motor shaft core before the ejector pin (205) clamps it; And an adjustment mechanism (3) for adjusting the spacing between the at least two shaft core placement platforms (4).

6. The device for precision straightening and residual stress relief of a motor shaft core according to claim 5, characterized in that, The adjustment mechanism (3) includes: A bidirectional lead screw (302) is rotatably mounted on the bracket (1); And at least two sliders (301), the sliders (301) being threaded to both ends of the bidirectional lead screw (302), and the shaft core placement platform (4) being fixed on the sliders (301).

7. The device for precision straightening and residual stress relief of a motor shaft core according to claim 6, characterized in that, The adjusting mechanism (3) further includes a rotating rod (304), a driving bevel gear (305), and a transmission bevel gear (303). The rotating rod (304) is connected to the driving bevel gear (305), the driving bevel gear (305) meshes with the transmission bevel gear (303), and the transmission bevel gear (303) is coaxially connected to the bidirectional lead screw (302) for driving the bidirectional lead screw (302) to rotate.

8. The device for precision straightening and residual stress relief of a motor shaft core according to claim 4, characterized in that, The correction mechanism (2) further includes a hydraulic lifting rod (203), which is mounted on the sliding base (201) and moves together with the sliding base (201).

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