High-power motorized spindle research and development test platform for numerical control machine tool

Abstract

The utility model provides a high-power motorized spindle research and development test platform for a numerical control machine tool, which comprises a motorized spindle system, an electric dynamometer, a test bench and monitoring and measuring equipment, and can be used for no-load test and loading test of a motorized spindle prototype, function test of a motorized spindle driving controller and performance verification. According to the utility model, the air compressor introduces the dried and filtered compressed gas into the oil-gas lubricating equipment to produce oil-gas mixed gas flow to lubricate and cool a high-speed bearing in the motorized spindle prototype, and the oil-gas mixed gas flow can be used for a high-speed or ultra-high-speed motorized spindle loading test.

Description

Technical Field

[0001] The utility model relates to the research and development field of high-power electric spindles for high-end CNC machine tools, in particular to a research and development and testing platform for high-power electric spindles for CNC machine tools. Background Art

[0002] The integration and integration of parts are driving the demand for large-scale machine tools, and the trend towards larger parts leads to parts with multiple machining surfaces. High-speed, high-power electric spindles used in CNC machine tools can achieve machining in a wide speed regulation range, and can almost complete all rough machining and fine machining of parts after clamping the workpiece once. Therefore, high-speed, high-power electric spindles have become a research hotspot. However, the design of traditional electric spindle test platforms is not compatible with the testing of electric spindles of different power levels and speed levels. The fault tolerance of the test bench is poor, and axis alignment and equipment adjustment are difficult. In the research and development process, using actual cutting to verify product performance is extremely costly. Building a simulation test platform to evaluate whether the technical parameters of the R&D product meet the design indicators is the most economical and reasonable solution. Utility Model Content

[0003] In order to solve the above-mentioned technical problems, the present invention provides a high-power electric spindle research and development test platform for CNC machine tools, which can be applied to multiple working condition tests such as high-speed high power, low-speed high power, and high-speed low power. The test bench has good fault tolerance and can achieve offset compensation in both angular and axial directions. Flexible connections are easier to achieve axis alignment and equipment adjustment than rigid connections. The present invention can be used for no-load testing and loading testing of electric spindle prototypes, and functional testing and performance verification of electric spindle drive controllers. In the present invention, the air compressor introduces dried and filtered compressed gas into the oil-gas lubrication equipment to create an oil-gas mixed flow to lubricate and cool the high-speed bearings in the electric spindle prototype, which can be used for high-speed or ultra-high-speed electric spindle loading testing.

[0004] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0005] A high-power electric spindle research and development and testing platform for CNC machine tools comprises an electric spindle system, an electric dynamometer, a test bench, and monitoring and measuring equipment. The electric spindle drive controller of the electric spindle system is connected to a bidirectional DC power supply of the electric dynamometer, the dynamometer motor of the electric dynamometer is connected to one end of a first diaphragm coupling of the test bench, an electric spindle prototype of the electric spindle system is connected to an HSK interface flange tool holder of the test bench, the first diaphragm coupling and the second diaphragm coupling of the test bench are connected to a torque and speed meter of the monitoring and measuring equipment, the electric spindle drive controller of the electric spindle system is connected to a current sensor and a power analyzer of the monitoring and measuring equipment, and the electric spindle prototype of the electric spindle system is connected to a vibration sensor and a temperature sensor of the monitoring and measuring equipment.

[0006] Furthermore, the output shaft of the dynamometer motor is connected to the torque and speed meter through a first diaphragm coupling, and the first diaphragm coupling compensates for the expansion and contraction of the output shaft of the dynamometer motor in the axial direction; the other end of the torque and speed meter is connected to the low-speed shaft of the high-speed gearbox through a second diaphragm coupling of the same specification, and the second diaphragm coupling compensates for the expansion and contraction of the low-speed shaft of the high-speed gearbox in the axial direction; the high-speed shaft of the high-speed gearbox is connected to the HSK interface flange tool holder through a diaphragm coupling; the HSK interface flange tool holder is connected to the output shaft of the electric spindle prototype, and the electric spindle prototype is connected to the horizontal iron base through the electric spindle clamping mechanism.

[0007] Furthermore, the electric spindle system includes an electric spindle drive controller, an electric spindle prototype, a water cooler, an oil-gas lubrication device, and an air compressor; the air compressor introduces compressed gas with a dry pressure dew point of ≤3°C, a filtration grade of ≤5μm, and a pressure of ≥0.5MPa into the oil-gas lubrication device to produce a 20mm³ / beat oil-gas mixed flow to lubricate and cool the high-speed bearings in the electric spindle prototype; the water cooler exchanges heat with the motor stator in the electric spindle prototype, the water inlet flow rate is ≥15L / min, the water inlet filtration accuracy is ≤400μm, and the cooling capacity is ≥10KW; the electric spindle drive controller controls the speed and torque of the electric spindle prototype through closed-loop feedback of the magnetic encoder.

[0008] Furthermore, the electric dynamometer includes a power input cabinet, a rectifier transformer, a rectifier unit, a bidirectional DC power supply, a dynamometer controller, and a dynamometer motor; adopts a common DC bus operation mode, and the three-phase AC power is rectified into a high-voltage DC power of ≥1000V through the power input cabinet, the rectifier transformer, and the rectifier unit. The bidirectional DC power supply is connected to the electric spindle drive controller, and the dynamometer controller drives the dynamometer motor to control the direction and magnitude of the loading torque, and suddenly increases or decreases in the torque direction to simulate the torsional vibration of the shaft system and the electromechanical coupling vibration.

[0009] Furthermore, the diaphragm coupling is integrally formed from 60Si2Mn spring steel, and can achieve a maximum offset compensation of 0.25° in the angular direction and a maximum telescopic compensation of 0.8mm in the axial direction.

[0010] Furthermore, the high-speed gearbox flexibly adjusts the installation method according to actual test requirements. When used in the forward direction as a reducer, a high-speed, high-power electric spindle loading test is carried out; when the dynamometer motor loads torque in the same direction, a high-speed, low-power electric spindle loading test is carried out; when the high-speed gearbox is used in the reverse direction as a speed increaser, a low-speed, high-power motor loading test is carried out.

[0011] Furthermore, the high-speed gearbox is equipped with an oil cooling circulation system consisting of an oil tank, an oil pump, and a heat exchanger to meet the heat dissipation requirements of high-speed and high-power loading tests.

[0012] Furthermore, one end of the HSK interface flange handle is one end of the HSK interface, and the other end is a flange. The installation size of the flange matches the flange installation size of the diaphragm coupling and is fixed with 42CrMo bolts and self-locking nuts. Beneficial effects

[0013] 1. The traditional test platform based on electric dynamometer is not equipped with oil and gas lubrication equipment, and cannot perform high-speed or ultra-high-speed electric spindle tests. In the utility model, the air compressor introduces the dried and filtered compressed gas into the oil and gas lubrication equipment to create an oil-gas mixed flow to lubricate and cool the high-speed bearings in the electric spindle prototype, which can be used for high-speed or ultra-high-speed electric spindle loading tests.

[0014] 2. In traditional test platforms, the test bench is connected by ordinary rigid couplings, which have poor fault tolerance. In the utility model, two sets of diaphragm couplings are used to compensate for the axial expansion and contraction of the dynamometer motor output shaft and the high-speed gearbox low-speed shaft respectively. The diaphragm coupling is integrally formed from 60Si2Mn spring steel, achieving a maximum 0.25° offset compensation in the angular direction and a maximum 0.8mm expansion and contraction compensation in the axial direction. Flexible connections are easier to achieve axis alignment and equipment adjustment than rigid connections.

[0015] 3. The traditional electric spindle test platform design is not compatible with electric spindle tests of different power levels and speed levels. The high-speed gearbox of the utility model can be flexibly adjusted according to actual test requirements. When used in the forward direction as a reducer, it can perform high-speed, high-power electric spindle loading tests; when the dynamometer motor is loaded with torque in the same direction, the torque of the same direction loading can play a boosting role, overcoming the large inertia of the dynamometer motor itself, and can perform high-speed, low-power electric spindle loading tests; when the high-speed gearbox is used in the reverse direction as a speed increaser, it can perform low-speed, high-power motor loading tests.

[0016] 4. Traditional HSK tool ends feature high-speed cutting blades, making them unsuitable for direct load testing on test platforms. This new design improves upon this approach, retaining the original HSK interface on one end while replacing the standard tool's high-speed cutting blade with a flange on the other. This custom-fabricated flange's mounting dimensions match those of the diaphragm coupling and is secured with 42CrMo bolts and self-locking nuts. The advantage is that for different types of electric spindles, only the corresponding HSK flange shank size is required, eliminating the need for any modification or damage to the spindle itself. This eliminates external interference factors and allows for a more accurate assessment of whether the product's technical parameters meet design specifications. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of a research and development test platform for a high-power electric spindle for CNC machine tools of the present invention;

[0018] Figure 2 Schematic diagram of the test bench.

[0019] Among them, the accompanying drawings are marked as: horizontal iron base 1, dynamometer motor 2, first diaphragm coupling 3, torque speed meter 4, second diaphragm coupling 5, high-speed gearbox 6, diaphragm disc coupling 7, HSK interface flange tool holder 8, electric spindle clamping mechanism 9, electric spindle prototype 10. DETAILED DESCRIPTION

[0020] To make the purpose, technical solutions, and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are intended only to illustrate the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other. The present invention is described in detail below with reference to the accompanying drawings.

[0021] like Figure 1 As shown, the high-power electric spindle R&D and testing platform for CNC machine tools of the present invention includes an electric spindle system, an electric dynamometer, a test bench, and monitoring and measuring equipment. The electric spindle drive controller of the electric spindle system is connected to the bidirectional DC power supply of the electric dynamometer. The dynamometer motor 2 of the electric dynamometer is connected to one end of the first diaphragm coupling 3 of the test bench. The electric spindle prototype 10 of the electric spindle system is connected to the HSK interface flange tool holder 8 of the test bench. The first diaphragm coupling 3 and the second diaphragm coupling 5 of the test bench are connected to the torque and speed meter 4 of the monitoring and measuring equipment. The electric spindle drive controller of the electric spindle system is connected to the current sensor and power analyzer of the monitoring and measuring equipment. The electric spindle prototype 10 of the electric spindle system is connected to the vibration sensor and temperature sensor of the monitoring and measuring equipment.

[0022] The electric spindle system includes an electric spindle drive controller, an electric spindle prototype, a water cooler, an oil-gas lubrication device, and an air compressor. The air compressor directs compressed air with a dry pressure dew point of ≤3°C, a filtration grade of ≤5μm, and a pressure of ≥0.5MPa into the oil-gas lubrication device, producing a 20mm³ / cycle oil-gas mixed flow to lubricate and cool the high-speed bearings in the electric spindle prototype 10. The water cooler exchanges heat with the motor stator in the electric spindle prototype 10, with an inlet water flow rate of ≥15L / min, an inlet water filtration accuracy of ≤400μm, and a cooling capacity of ≥10kW. The electric spindle drive controller controls the speed and torque of the electric spindle prototype via closed-loop feedback from a magnetic encoder.

[0023] The electric dynamometer includes a power input cabinet, a rectifier transformer, a rectifier unit, a bidirectional DC power supply, a dynamometer controller, and a dynamometer motor. Operating in a common DC bus mode, three-phase AC power is rectified into high-voltage DC power (≥1000V) via the power input cabinet, rectifier transformer, and rectifier unit. The bidirectional DC power supply is connected to the electric spindle drive controller, which drives the dynamometer motor. The dynamometer controller can control the direction and magnitude of the loading torque, and can increase or decrease the torque in the direction of the torque to simulate shaft torsional vibration and electromechanical coupling vibration.

[0024] The monitoring and measurement equipment includes a current sensor, power analyzer, vibration sensor, temperature sensor, and torque / tachometer to monitor the changes in various parameters during the test. The torque / tachometer 4 inputs the torque / tachometer into the power analyzer, which then performs power analysis based on the voltage from the electric spindle drive controller and the current from the current sensor.

[0025] The test bench includes two diaphragm couplings, a high-speed gearbox 6, an oil tank, an oil pump, a heat exchanger, a diaphragm coupling 7, and an HSK interface flange tool holder 8. Figure 2 As shown, the test bench is based on a horizontal iron base 1, upon which are mounted a dynamometer motor 2, a first diaphragm coupling 3, a torque and speed meter 4, a second diaphragm coupling 5, a high-speed gearbox 6, a diaphragm coupling 7, an HSK interface flange tool holder 8, an electric spindle clamping mechanism 9, and an electric spindle prototype 10. The output shaft of the dynamometer motor 2 is connected to the torque and speed meter 4 via the first diaphragm coupling 3, which compensates for axial expansion and contraction of the dynamometer motor 2's output shaft. The other end of the torque and speed meter 4 is connected to the low-speed shaft of the high-speed gearbox 6 via a second diaphragm coupling 5 of the same specifications, which compensates for axial expansion and contraction of the low-speed shaft of the high-speed gearbox 6. The high-speed shaft of the high-speed gearbox 6 is connected to the HSK interface flange tool holder 8 via the diaphragm coupling 7. The high-speed gearbox 6 is equipped with an oil cooling circulation system consisting of an oil tank, an oil pump, and a heat exchanger, which can meet the heat dissipation requirements of high-speed and high-power loading tests; the HSK interface flange tool holder 8 is connected to the output shaft of the electric spindle prototype 10, and the electric spindle prototype 10 is connected to the horizontal iron base 1 through the electric spindle clamping mechanism 9.

[0026] Preferably, the diaphragm coupling 7 is integrally formed from 60Si2Mn spring steel, and can achieve a maximum 0.25° offset compensation in the angular direction and a maximum 0.8mm telescopic compensation in the axial direction. Flexible connections are easier to achieve axis centering and equipment adjustment than rigid connections.

[0027] The HSK interface is an ISO standard interface for high-speed cutting tools. HSK stands for the German abbreviation for Hohl Shaft Kegel. The International Organization for Standardization promulgated the official ISO standard for the HSK tool system, ISO 12164, in 2001. Traditional HSK tool ends feature a high-speed cutting blade, making them unsuitable for direct load testing on test benches. The present invention improves upon this traditional HSK tool end, retaining the original HSK interface at one end while replacing the high-speed cutting blade in the standard tool with a flange at the other end. This custom-made flange's mounting dimensions match those of the diaphragm coupling 7 and is secured with 42CrMo bolts and self-locking nuts. The advantage is that for different types of electric spindles, only the corresponding HSK flange shank needs to be replaced. No modification or damage to the electric spindle itself is required, eliminating external interference factors and enabling a more accurate assessment of whether the technical parameters of the developed product meet design specifications.

[0028] The high-speed gearbox 6 can flexibly adjust the installation method according to actual test requirements. When used in the forward direction as a reducer, a high-speed, high-power electric spindle loading test can be carried out; when the dynamometer motor 2 is loaded with torque in the same direction, the torque loaded in the same direction can play a supporting role, overcoming the large inertia of the dynamometer motor 2 itself, and a high-speed, low-power electric spindle loading test can be carried out; when the high-speed gearbox 6 is used in the reverse direction as a speed increaser, a low-speed, high-power motor loading test can be carried out.

Claims

1. A high-power electric spindle R&D and testing platform for CNC machine tools, characterized by: The invention comprises an electric spindle system, an electric dynamometer, a test bench and a monitoring and measuring device; the electric spindle drive controller of the electric spindle system is connected to the bidirectional DC power supply of the electric dynamometer, the dynamometer motor of the electric dynamometer is connected to one end of the first diaphragm coupling of the test bench, the electric spindle prototype of the electric spindle system is connected to the HSK interface flange tool holder of the test bench, the first diaphragm coupling and the second diaphragm coupling of the test bench are connected to the torque and speed meter of the monitoring and measuring device, the electric spindle drive controller of the electric spindle system is connected to the current sensor and the power analyzer of the monitoring and measuring device, and the electric spindle prototype of the electric spindle system is connected to the vibration sensor and the temperature sensor of the monitoring and measuring device.

2. A high-power electric spindle R&D and testing platform for CNC machine tools according to claim 1, characterized in that: The output shaft of the dynamometer motor is connected to the torque and speed meter through a first diaphragm coupling, and the first diaphragm coupling compensates for the expansion and contraction of the output shaft of the dynamometer motor in the axial direction; the other end of the torque and speed meter is connected to the low-speed shaft of the high-speed gearbox through a second diaphragm coupling of the same specification, and the second diaphragm coupling compensates for the expansion and contraction of the low-speed shaft of the high-speed gearbox in the axial direction; the high-speed shaft of the high-speed gearbox is connected to the HSK interface flange tool holder through a diaphragm coupling; the HSK interface flange tool holder is connected to the output shaft of the electric spindle prototype, and the electric spindle prototype is connected to the horizontal iron base through the electric spindle clamping mechanism.

3. The high-power electric spindle R&D and testing platform for CNC machine tools according to claim 1 is characterized by: The electric spindle system includes an electric spindle drive controller, an electric spindle prototype, a water cooler, an oil-gas lubrication device, and an air compressor. The air compressor introduces compressed gas with a dry pressure dew point of ≤3°C, a filtration grade of ≤5μm, and a pressure of ≥0.5MPa into the oil-gas lubrication device to produce a 20mm³ / beat oil-gas mixed flow to lubricate and cool the high-speed bearings in the electric spindle prototype. The water cooler exchanges heat with the motor stator in the electric spindle prototype, with a water inlet flow rate of ≥15L / min, a water inlet filtration accuracy of ≤400μm, and a cooling capacity of ≥10kW. The electric spindle drive controller controls the speed and torque of the electric spindle prototype through closed-loop feedback from a magnetic encoder.

4. The high-power electric spindle R&D and testing platform for CNC machine tools according to claim 1 is characterized by: The electric dynamometer includes a power input cabinet, a rectifier transformer, a rectifier unit, a bidirectional DC power supply, a dynamometer controller, and a dynamometer motor; it adopts a common DC bus operation mode, and the three-phase AC power is rectified into high-voltage DC power of ≥1000V through the power input cabinet, the rectifier transformer, and the rectifier unit. The bidirectional DC power supply is connected to the electric spindle drive controller, and the dynamometer controller drives the dynamometer motor to control the direction and magnitude of the loading torque, and suddenly increases or decreases in the torque direction to simulate shaft torsional vibration and electromechanical coupling vibration.

5. The high-power electric spindle R&D and testing platform for CNC machine tools according to claim 2, characterized in that: The diaphragm coupling is integrally formed from 60Si2Mn spring steel and can achieve a maximum offset compensation of 0.25° in the angular direction and a maximum telescopic compensation of 0.8mm in the axial direction.

6. The high-power electric spindle R&D and testing platform for CNC machine tools according to claim 2, characterized in that: The high-speed gearbox adjusts its installation method according to actual test requirements. When used in the forward direction as a reducer, a high-speed, high-power electric spindle loading test is carried out; when the dynamometer motor loads torque in the same direction, a high-speed, low-power electric spindle loading test is carried out; when the high-speed gearbox is used in the reverse direction as a speed increaser, a low-speed, high-power motor loading test is carried out.

7. The high-power electric spindle R&D and testing platform for CNC machine tools according to claim 2, characterized in that: The high-speed gearbox is equipped with an oil cooling circulation system consisting of an oil tank, an oil pump, and a heat exchanger to meet the heat dissipation requirements of high-speed and high-power loading tests.

8. The high-power electric spindle R&D and testing platform for CNC machine tools according to claim 2, characterized in that: One end of the HSK interface flange handle is one end of the HSK interface, and the other end is a flange. The installation size of the flange matches the flange installation size of the diaphragm coupling and is fixed with 42CrMo bolts and self-locking nuts.

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