A piezoelectric ceramic-based bearing pre-tightening force intelligent regulation and control assembly

Abstract

The application relates to a bearing pre-tightening force intelligent regulation and control assembly based on piezoelectric ceramics. The technical scheme is as follows: a shell, an inner ring, columnar piezoelectric ceramics, a driving power supply, a guide ring, a micro pressure sensor, a data acquisition card and a control system are arranged; the bottom end of the inner ring is fixedly connected with the bottom wall of the shell, a ring cavity is formed between the inner ring and the shell, a plurality of columnar piezoelectric ceramics are uniformly arranged in the ring cavity, and the bottom end of the columnar piezoelectric ceramic is connected with the bottom wall of the shell; a plurality of micro pressure sensors are arranged on the bottom surface of the guide ring, the guide ring is located between the inner ring and the shell, the columnar piezoelectric ceramic and the micro pressure sensor are coaxially arranged; the driving power supply and the micro pressure sensor are connected with the data acquisition card, the data acquisition card is connected with the control system, and the driving power supply is used for driving the columnar piezoelectric ceramic. The application utilizes the precise displacement and force output characteristics of the piezoelectric ceramic to realize real-time monitoring and intelligent regulation and control of the running state of the main shaft bearing in the speed range and the pre-tightening force.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of machinery, and particularly relates to a bearing pre-tightening force intelligent regulation and control assembly based on piezoelectric ceramics. BACKGROUND

[0002] Piezoelectric ceramics have the advantages of large output power, high control precision and fast response speed, and can realize precise displacement output and accurate force output.

[0003] Pre-tightening force, as an important parameter of a bearing system, directly affects the performance of a rotor system such as an electric spindle and a motor. At present, the traditional pre-tightening force applying mode is mainly determined by a recommended pre-tightening value of a bearing manufacturer according to the rotation speed, cutting load, driving mode, lubrication and cooling mode of the spindle. This mode is selected by experience, lacks accurate standards, and cannot adjust the running state of the bearing in real time according to the actual working condition of the spindle. Therefore, the spindle cannot exert optimal performance under different working conditions, and cannot guarantee the dynamic and thermal state characteristics of the spindle system in the entire rotation speed range. If a pre-tightening force active control unit is integrated on the spindle to intelligently adjust the pre-tightening force of the bearing, the same spindle can adapt to different working conditions, and the optimal pre-tightening force under the working condition can be applied to the spindle rotor system in real time, which can effectively suppress spindle vibration, reduce working temperature, improve spindle stiffness and service life, exert the optimal performance of the bearing under different working conditions, and has very important engineering significance. SUMMARY

[0004] The application provides a bearing pre-tightening force intelligent regulation and control assembly based on piezoelectric ceramics, which utilizes the precise displacement and force output characteristics of piezoelectric ceramics to monitor and intelligently regulate the running state of the spindle bearing in the rotation speed range in real time, and can analyze the influence of the pre-tightening force on the bearing performance under different working conditions, thereby providing a theoretical basis for improving the machining precision of the electric spindle system and the research and development of the intelligent spindle.

[0005] The technical scheme of the application is as follows:

[0006] The application discloses a bearing pre-tightening force intelligent control assembly based on piezoelectric ceramics, which comprises a shell, an inner ring, columnar piezoelectric ceramics, a driving power supply, a guide ring, micro pressure sensors, a data acquisition card and a control system, the bottom end of the inner ring is fixedly connected with the bottom wall of the shell, a ring cavity is formed between the inner ring and the shell, a plurality of columnar piezoelectric ceramics are uniformly arranged in the ring cavity, and the bottom end of the columnar piezoelectric ceramic is connected with the bottom wall of the shell; a plurality of micro pressure sensors are arranged on the bottom surface of the guide ring, the guide ring is located between the inner ring and the shell, the columnar piezoelectric ceramic and the micro pressure sensor are coaxially arranged in one-to-one correspondence, and the micro pressure sensor is used for monitoring the pre-tightening force of the bearing in real time; the driving power supply and the micro pressure sensor are connected with the data acquisition card, the data acquisition card is connected with the control system, and the driving power supply is used for driving the columnar piezoelectric ceramic.

[0007] Further, the bearing pre-tightening force intelligent control assembly based on piezoelectric ceramics, the guide ring is composed of three guide blocks, and the bottom surface of the guide block is provided with a position hole; the number of columnar piezoelectric ceramics and micro pressure sensors is three, and the micro pressure sensor is placed in the position hole.

[0008] Further, the bearing pre-tightening force intelligent control assembly based on piezoelectric ceramics, the bottom end of the columnar piezoelectric ceramic is provided with an adjusting bolt, the bottom wall of the shell is provided with a threaded hole, and the adjusting bolt is screwed into the threaded hole.

[0009] Further, the bearing pre-tightening force intelligent control assembly based on piezoelectric ceramics, the guide ring is in clearance fit with the shell; and the top end of the inner ring is externally provided with an annular clamping edge, and the annular clamping edge axially limits the guide ring.

[0010] Further, the bearing pre-tightening force intelligent control assembly based on piezoelectric ceramics is provided with an eddy current displacement sensor, the bottom wall of the shell is provided with a threaded hole one, the guide ring is provided with a detection hole one, the bottom end of the eddy current displacement sensor is provided with an external thread screwed into the threaded hole one, and the top end of the eddy current displacement sensor is placed in the detection hole one; the eddy current displacement sensor is connected with the data acquisition card through a wire and is used for monitoring the displacement of the bearing outer ring in real time.

[0011] Further, the bearing pre-tightening force intelligent control assembly based on piezoelectric ceramics is provided with a non-contact infrared temperature measuring instrument, the bottom wall of the shell is provided with a threaded hole two, the guide ring is provided with a detection hole two, the bottom end of the non-contact infrared temperature measuring instrument is provided with an external thread screwed into the threaded hole two, and the top end of the non-contact infrared temperature measuring instrument is placed in the detection hole two; the non-contact infrared temperature measuring instrument is connected with the data acquisition card through a wire and is used for monitoring the temperature of the bearing outer ring in real time.

[0012] Further, the piezoceramic-based bearing pre-tightening force intelligent control assembly is provided with a non-contact vibration sensor, a threaded hole three is arranged on the side wall of the shell, the inner ring is provided with a detection hole three, the bottom end of the non-contact vibration sensor is provided with an external thread screwed into the threaded hole three, and the top end of the non-contact vibration sensor penetrates through the detection hole three; the non-contact vibration sensor is connected with the data acquisition card through wires, and is used for monitoring the vibration condition of the main shaft in real time.

[0013] In the working state, the shell and the bearing seat are fixedly installed together, and the guide ring is on the bearing outer ring. When the control system monitors that the working condition of the main shaft needs larger pre-tightening force, the control driving power supply increases the output voltage to the cylindrical piezoelectric ceramic, the cylindrical piezoelectric ceramic is elongated to receive a pulse signal, the guide ring is pushed, the guide ring slides forward between the shell and the inner ring, the force output by the cylindrical piezoelectric ceramic is transmitted to the bearing outer ring, the bearing clearance is reduced, and then the pre-tightening force of the main shaft is increased. When the control system monitors that the working condition of the main shaft needs smaller pre-tightening force, the control driving power supply reduces the output voltage to the cylindrical piezoelectric ceramic, the cylindrical piezoelectric ceramic is shortened to receive a pulse signal, the guide ring retreats, the bearing outer ring is relaxed, the bearing clearance is increased, and the pre-tightening force of the main shaft is reduced.

[0014] The piezoceramic-based bearing pre-tightening force intelligent control assembly has the following beneficial effects:

[0015] 1. The piezoceramic-based bearing pre-tightening force intelligent control assembly can complete the analysis of the influence of pre-tightening force on bearing performance under different working conditions, facilitate real-time monitoring of bearing pre-tightening force, axial displacement and temperature, provide technical support for designing a bearing pre-tightening force control system that is efficient, stable and fast in response, and provide a theoretical basis for improving the machining precision of an electric spindle system and the research and development of an intelligent spindle.

[0016] 2. The adjusting bolt connects the cylindrical piezoelectric ceramic and the shell, can finely adjust the mounting process of the cylindrical piezoelectric ceramic, and ensures that the three cylindrical piezoelectric ceramics uniformly load the guide ring.

[0017] 3. The miniature pressure sensor, the non-contact vibration sensor, the non-contact infrared temperature measuring instrument and the eddy current displacement sensor monitor the bearing operation in real time, and the control system can change the force output to the bearing outer ring according to the actual working condition. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 It is a schematic diagram of the piezoceramic-based bearing pre-tightening force intelligent control assembly.

[0019] Figure 2 It is a schematic diagram of the internal structure of the piezoceramic-based bearing pre-tightening force intelligent control assembly.

[0020] Figure 3 It is a sectional view of the piezoceramic-based bearing pre-tightening force intelligent control assembly (the shell is not shown).

[0021] Figure 4 This is a schematic diagram showing the usage status of a bearing preload intelligent control component based on piezoelectric ceramics. Detailed Implementation

[0022] like Figures 1-4 As shown, a bearing preload intelligent control component based on piezoelectric ceramics includes a housing 1, an inner ring 2, cylindrical piezoelectric ceramics 4, a drive power supply 15, a guide ring 7, a miniature pressure sensor 5, a non-contact vibration sensor 9, a non-contact infrared thermometer 6, an eddy current displacement sensor 8, a data acquisition card 16, and a control system 14. The bottom end of the inner ring 2 is fixedly connected to the bottom wall of the housing 1, forming an annular cavity between the inner ring 2 and the housing 1. Three cylindrical piezoelectric ceramics 4 are evenly arranged in the annular cavity, and the bottom end of each cylindrical piezoelectric ceramic 4 is provided with an adjusting bolt 3. The bottom wall of the housing 1 is provided with a threaded through hole, and the adjusting bolt 3 is screwed into the threaded through hole. The guide ring 7 is composed of three guide blocks connected together, forming a ring structure that is easy to disassemble. Each guide block has a position hole on its bottom surface, and a miniature pressure sensor 5 is placed in the position hole. The guide ring 7 is located between the inner ring 2 and the housing 1, and the guide ring 7 is clearance-fitted with the housing 1. The guide ring 7 can move linearly along the axial direction of the housing 1. The top of the inner ring 2 has an annular retaining edge, which limits the axial movement of the guide ring 7. The cylindrical piezoelectric ceramic 4 and the miniature pressure sensor 5 are arranged coaxially in a one-to-one correspondence. The miniature pressure sensor 5 is used to monitor the preload of the bearing 18 in real time. The driving power supply 15 and the miniature pressure sensor 5 are connected to the data acquisition card 16. The data acquisition card 16 is connected to the control system 14. The driving power supply 15 is used to drive the cylindrical piezoelectric ceramic 4.

[0023] The bottom wall of the housing 1 has a threaded hole, and the guide ring 7 has a detection hole. The bottom end of the eddy current displacement sensor 8 has an external thread that screws into the threaded hole, and the top end of the eddy current displacement sensor 8 is placed in the detection hole. The eddy current displacement sensor 8 is connected to the data acquisition card 16 via a wire for real-time monitoring of the displacement of the bearing outer ring. The bottom wall of the housing 1 also has a threaded hole, and the guide ring 7 has a detection hole. The bottom end of the non-contact infrared thermometer 6 has an external thread that screws into the threaded hole, and the top end of the non-contact infrared thermometer 6 is placed in the detection hole. The non-contact infrared thermometer 6 is connected to the data acquisition card 16 via a wire for real-time monitoring of the temperature of the bearing outer ring. The side wall of the housing 1 is provided with a threaded hole three, the inner ring 2 is provided with a detection hole three, the bottom end of the non-contact vibration sensor 9 is provided with an external thread that is screwed into the threaded hole three, and the top end of the non-contact vibration sensor 9 passes through the detection hole three; the non-contact vibration sensor 9 is connected to the data acquisition card 16 through a wire to monitor the vibration of the spindle 13 in real time.

[0024] As Figure 4 shown, the main shaft 13 is provided on the vibration isolation platform 12, the servo motor 10 is connected with the main shaft 13 through the flexible coupling 11, and the servo motor 10 is connected with the data acquisition card 16 through wires; the shell 1 is fastened with the bearing seat 17 through bolts, the head of the guide ring 7 is inserted into the bearing seat 17 and clamped with the outer ring of the bearing; after the assembly of the main shaft 13 is completed, the connection between the control system 14 and the driving power supply 15, the data acquisition card 16, the micro pressure sensor 5, the non-contact infrared temperature measuring instrument 6, the eddy current displacement sensor 8 and the non-contact vibration sensor 9 is completed; the driving power supply 15 and the control system 14 interface are started respectively, according to the given working speed, the control system 14 calculates the optimal pre-tightening force of the bearing 18 under the working condition, the cylindrical piezoelectric ceramic 4 acts, the guide ring 7 generates axial displacement, and the bearing outer ring pushes the rotor to exert axial pre-tightening force; the indications of the three groups of micro pressure sensors 5 in the control system 14 are observed, if the indications are different, the adjusting bolts 3 can be finely adjusted until the indications are equal, so as to ensure the uniform loading of the bearing 18.

[0025] When the main shaft 13 runs at low speed, the data acquisition card 16 collects the working frequency of the servo motor 10, that is, the working speed of the bearing 18, at this time, the control system 14 detects that the working speed of the current bearing 18 is low, and calculates a larger optimal pre-tightening force matched with the working speed, and then controls the driving power supply 15 to accurately output voltage to the three groups of cylindrical piezoelectric ceramics 4, the cylindrical piezoelectric ceramics 4 receive pulse signals to elongate, push the guide ring 7, the guide ring 7 slides forward between the shell 1 and the inner ring 2, the force output by the cylindrical piezoelectric ceramic 4 is transmitted to the bearing outer ring, the pre-tightening force of the bearing 18 is increased, the system stiffness of the main shaft 13 is improved, and the requirements of the low-speed heavy cutting working condition are met.

[0026] When the main shaft 13 runs at high speed, the data acquisition card 16 collects the working frequency of the servo motor 10, that is, the working speed of the bearing 18, at this time, the control system 14 detects that the working speed of the current bearing 18 is high, and calculates a smaller optimal pre-tightening force matched with the working speed, and then controls the driving power supply 15 to accurately output voltage to the three groups of cylindrical piezoelectric ceramics 4, the cylindrical piezoelectric ceramics 4 receive pulse signals to shorten, the guide ring 7 slides backward between the shell 1 and the inner ring 2, the force output to the bearing outer ring is reduced, thereby the pre-tightening force of the bearing 18 is reduced, the system temperature rise of the main shaft 13 is reduced, the service life of the main shaft 13 is prolonged, and the requirements of the high-speed light cutting working condition are met.

Claims

1. A piezoceramic-based bearing pre-tightening force intelligent control assembly, characterized in that, The utility model relates to a kind of piezoelectric ceramic motor, including shell, inner ring, cylindrical piezoelectric ceramic, drive power supply, guide ring, micro pressure sensor, data acquisition card and control system, the bottom of the inner ring is fixedly connected with the bottom wall of the shell, ring cavity is formed between the inner ring and the shell, multiple cylindrical piezoelectric ceramics are evenly arranged in the ring cavity, the bottom of cylindrical piezoelectric ceramic is connected with the bottom wall of the shell;The bottom of the guide ring is equipped with multiple micro pressure sensors, the guide ring is located between the inner ring and the shell, the guide ring is used to insert bearing seat and the bearing outer ring of jamming, cylindrical piezoelectric ceramic and micro pressure sensor are coaxially arranged one by one;The drive power supply and micro pressure sensor are connected with the data acquisition card, the data acquisition card is connected with the control system, and the drive power supply is used to drive cylindrical piezoelectric ceramic; The guide ring is composed of three guide blocks, the bottom of the guide block is equipped with a position hole;The number of cylindrical piezoelectric ceramic and micro pressure sensor is three, and micro pressure sensor is placed in the position hole;The bottom of the cylindrical piezoelectric ceramic is equipped with an adjusting bolt, the bottom wall of the shell is equipped with a threaded hole, and the adjusting bolt is screwed into the threaded hole;The guide ring is gap fitted with the shell;The top of the inner ring is equipped with an annular clamping edge, and the annular clamping edge is axially limited to the guide ring.

2. The piezoceramics-based bearing pre-tightening force intelligent regulating and controlling assembly according to claim 1, characterized in that, An eddy current displacement sensor is provided, a threaded hole one is formed in the bottom wall of the shell, a detection hole one is formed in the guide ring, an external thread of the bottom end of the eddy current displacement sensor is screwed into the threaded hole one, and the top end of the eddy current displacement sensor is placed in the detection hole one;The eddy current displacement sensor is connected with the data acquisition card through a wire. 3.The piezoceramics-based bearing pre-tightening force smart regulating component of claim 1, wherein, A non-contact infrared temperature measuring instrument is provided, a threaded hole two is formed in the bottom wall of the shell, a detection hole two is formed in the guide ring, an external thread of the bottom end of the non-contact infrared temperature measuring instrument is screwed into the threaded hole two, and the top end of the non-contact infrared temperature measuring instrument is placed in the detection hole two;The non-contact infrared temperature measuring instrument is connected with the data acquisition card through a wire.

4. The piezoceramic-based bearing pre-load smart regulation assembly of claim 1, wherein, A non-contact vibration sensor is provided, a threaded hole three is formed in the side wall of the shell, a detection hole three is formed in the inner ring, an external thread of the bottom end of the non-contact vibration sensor is screwed into the threaded hole three, and the top end of the non-contact vibration sensor passes through the detection hole three;The non-contact vibration sensor is connected with the data acquisition card through a wire.

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