CN102078974B - Air floatation high-speed electric main shaft - Google Patents

Abstract

The invention relates to an air floatation high-speed electric main shaft, in particular to an air floatation high-speed electric main shaft for a machining tool. A lower air bearing block assembly 7 is fixed on a thrust bearing 9, the upper part of the lower air bearing block assembly 7 is provided with a stator 6, the front end of a shaft core 5 is provided with a chuck accessory 11, an aluminum water jacket assembly 3 is fixed at the upper opening of a body assembly 10, and a tool changing cylinder assembly 1 is fixed on the upper part of the aluminum water jacket assembly 3; and the middle part of the shaft body of an upper air bearing 4 is provided with an upper air bearing cooling water passage 12. The main shaft is an electromechanical integrated base piece with high revolution number and high precision, has simple and compact structure, and is convenient to install, high in heat dissipation efficiency, multifunctional and convenient for popularization and application.

Description

An air-floating high-speed electric spindle

technical field

The invention relates to a mechanical processing equipment, in particular to an air-floating high-speed electric spindle used for precise processing of PCBs.

Background technique

In the prior art, the aluminum water jacket assembly for the air-floating high-speed electric spindle has a complex structure, which is not conducive to heat dissipation of the spindle, inconvenient installation, single function, and difficult to grasp the assembly accuracy. The bearing seat assembly has a single structure, difficult processing, inconvenient loading and unloading, low heat dissipation capacity, and large vibration amplitude. The spindle chuck attachment is used to fix the tail of the chuck and increase the stability of the chuck. However, when the spindle rotates at high speed, the shaft bull will rub against the inner wall of the shaft core. There are pistons and partitions in the cylinder body of the main shaft, so it is necessary to drill a number of screw holes on the outer wall of the cylinder to fix the partitions, so the cylinder body generally requires a certain thickness, which results in unnecessary production costs. Secondly, the diameter of the piston is reduced due to the increase in the thickness of the cylinder, which reduces the thrust of the piston and causes unnecessary energy consumption.

Contents of the invention

The invention relates to an air-floating high-speed spindle, which is a high-revolution, high-precision electromechanical integration basic part, with simple and compact structure, convenient installation, high heat dissipation efficiency, multiple functions, and easy popularization and application.

The technical solution of the present invention is to provide a gap isolation plate 8 on the radial periphery of the existing body assembly 10, the cylinder return spring 2, the upper air bearing 4, the shaft core 5, and the flange of the shaft core 5, and the gap isolation plate 8 On the basis that the thrust bearing 9 is fixed on the surface, the present invention is particularly that the lower air bearing seat assembly 7 is fixed on the thrust bearing 9, the upper part of the lower air bearing seat assembly 7 is provided with a stator 6, and the front end of the shaft core 5 is provided with a collet attachment 11 , the upper opening of the body assembly 10 is fixed with an aluminum water jacket assembly 3, and the upper part of the aluminum water jacket assembly 3 is fixed with a tool change cylinder assembly 1;

The lower air bearing housing assembly 7 described in the present invention includes a bearing housing 7.2, a radial outer water channel 7.7 on the middle side of the bearing boss of the bearing housing 7.2, and the upper and lower outer walls of the bearing boss near the outer water channel 7.7. A water-air seal ring 7.3 is provided, and an air seal ring 7.6 is provided on the periphery of the bearing boss. The near head end of the bearing boss and the place near the bearing seat 7.2 are all provided with a radially penetrating air passage 7.4, and the inner wall of the through hole in the bearing is provided with There is an inner bearing sleeve 7.1, and the head-to-tail joint between the inner bearing sleeve 7.1 and the inner wall of the through hole is provided with a vibration-damping sealing ring 7.5, and the middle part of the inner bearing sleeve 7.1 is provided with an inner water flow channel 7.8 communicated with the outer water flow channel 7.7, and the inner bearing The sleeve 7.1 is provided with an airflow outlet corresponding to the airflow passage 7.4 of the bearing boss, and a damping plug 7.9 is arranged at the airflow outlet.

The stator 6 of the present invention is provided with a water-cooling mechanism, and the mechanism includes a power cord 6.5. The outer wall of the stator 6 is provided with a water tank 6.3. It is divided into a water outlet area 6.7 and a water inlet area 6.6, and a water inlet and return isolation block 6.8 is provided between the water outlet area 6.7 and the water inlet area 6.6.

The above-mentioned aluminum water jacket assembly 3 includes the connecting seat 3.2 of the aluminum water jacket, the upper port of the connecting seat 3.2 and the outer wall near the bearing seat are provided with a sealing ring 3.1, and the middle part of the connecting seat 3.2 is provided with an axial through The outer wall of the connecting seat 3.2 between the two sealing rings 3.1 is provided with a cooling water tank 3.4, and the side wall of the connecting seat 3.1 is provided with a water inlet 3.9 communicating with the cooling water tank 3.4; the inner wall of the push rod hole is provided with There is at least one bearing bush 3.3; an air inlet 3.5 and a return hole 3.8 are respectively arranged on the side wall of the connection seat 3.2, both of which are connected with the bottom end surface of the connection seat 3.2; The air hole 3.7 and the power connector 3.6 are all connected with the inner cavity of the bearing seat, and the upper and lower ends of the push rod hole inner wall are provided with bearing bushes 3.3.

The tool change cylinder assembly 1 of the present invention comprises a cylinder body 1.4, the middle and lower parts of the outer wall of the cylinder body 1.4 are provided with exhaust holes, an air inlet nozzle 1.1, an upper baffle 1.6, a lower baffle 1.10, each baffle and Seal rings 1.7, top cover 1.3, and one or more pistons 1.9 are arranged between the inner walls of the cylinder body 1.4. A sealing ring 1.11, a notch 1.13 of an axial through hole is provided at the head end of the piston 1.9, a sealing ring 1.8 is provided between the piston 1.9 and the inner wall of the cylinder body 1.4, a through hole 1.14 is provided at the axial center of the piston 1.9, and the top of the through hole 1.14 The inner wall is provided with threads 1.16, and the inner wall of the top cover 1.3 and the upper surface of the upper partition 1.6 are provided with a retaining spring 1.5, and a screw 1.2 runs through the top cover 1.3, the upper partition 1.6 and the retaining spring 1.5; the cylinder body 1.4 is provided with an upper piston And the lower piston, the head end gap of the upper piston is set at the end of the axial through hole of the lower piston; the bottom of the cylinder body 1.4 is provided with a counterbore 1.12 to be fixed with the lower cylinder or the body; the middle part of the outer wall of the cylinder body 1.4 is provided with an exhaust hole 1.17, The lower part of the outer wall of the cylinder body 1.4 is provided with an exhaust hole 1.15; the head end of the air intake nozzle 1.1 is provided with a damping hole 1.18.

The collet attachment 11 described in the present invention above includes a shaft core 5, a shaft main body 11.2, a shaft main body jacket 11.3, a butterfly spring 11.4, a collet 11.5, and the outer wall of the shaft boss main body jacket 11.3 is provided with two lubricating oil grooves 11.6.

When the main shaft is working, connect the required pressure air from the air inlet of the machine body, and the pressure air will act on the shaft core after passing through the cut-off core of the air bearing and the thrust bearing, so that the shaft core is completely in a suspended state, so that there is no contact friction during rotation, and the maximum Reduce frictional loss and heat generation as much as possible; meet the requirements of cooling water from the water inlet of the body, and discharge it after circulating through the top of the thrust bearing, the upper air bearing water tank, the water channel in the inner and outer interlayer of the body and the lower air bearing water tank, and take away the motor to work The heat generated by time and air friction ensures the stable and reliable operation of the spindle; provides the motor stator with a three-phase AC variable frequency power supply that meets the requirements to drive the shaft core to rotate, and the chuck attachment at the bottom of the shaft core can hold various tools such as drill bits for High-efficiency, high-precision processing, the range of revolutions can be selected from 20,000-200,000/min according to specific requirements. When it is necessary to change the tool, supply compressed air to the top cylinder, the piston push rod pushes the shaft bull in the shaft core and compress the disc spring to move the chuck down and open, then remove the tool and install a new tool, and cut off the air supply to the cylinder The tool can be clamped automatically. If it is installed on an automatic machine tool for control, it can perform automatic high-speed and efficient processing. The main shaft is equipped with a temperature sensor and a speed sensor for corresponding feedback protection.

The advantages of the present invention are:

1. When working, use the variable frequency power supply to adjust the input frequency, so that the working speed can reach 200,000rpm, which meets the requirements of high-speed and high-precision processing;

2. When working, use compressed air to pass through the upper and lower air bearings and thrust bearings to completely float the shaft core without any contact with each part, which can minimize friction and provide guarantee for high speed. Due to the bearing seat and bearing The cooling water of the inner sleeve is directly cooled, and the distance between the bearing inner sleeve and the shaft core is very close, so the heat dissipation effect is good. The vibration damping seal ring is designed between the bearing housing and the bearing inner sleeve, which has good vibration damping effect, convenient installation and high operational reliability. ;

3. Turn on the coolant when working, and force the thrust bearing, air bearing and motor to cool down, take away the heat loss of the motor and the heat of air friction, and ensure the long-term stable operation of the spindle;

4. In order to meet the fast start-up performance and reduce the start-up inertia, the diameter of the shaft is appropriately reduced, but in order to ensure sufficient air bearing support force and rigidity, two sets of support structures are used on the upper and lower air bearing structures.

5. In order to reduce the impact of air friction heat on the accuracy of air bearings at high speeds, the upper and lower air bearings are directly cooled as a whole;

6. The cylinder can be used to automatically replace various required tools. The cylinder body has a compact structure. Since the outer wall of the cylinder does not need to be screw holes, it can be made as thin as possible to save materials. After the diameter of the cylinder body is determined, the internal piston can be cut. The diameter is the largest to generate the greatest thrust; the shaft block assembly is easy to install and disassemble, reducing friction as much as possible, making the whole movement smoother, high working efficiency, improving the life of the shaft core, ensuring assembly accuracy, simple processing, and high operational reliability;

7. The motor rotor is directly made of copper squirrel cage in the middle of the rotating shaft by special technology to realize the transmission in the middle to make the structure more reasonable and compact. At the same time, the power loss and temperature rise of the rotating shaft are greatly reduced compared with the steel solid rotor, and it is also more conducive to reliable work at high speeds;

8. Adopt reasonable processing technology route and precision processing means, cooperate with necessary special technology to ensure product realization and quality;

9. The design of the overall water channel is flexible and ingenious. The upper and lower bearings, stator and aluminum water jacket components are directly cooled. Compared with the previous structure, the cooling effect has been significantly improved. The phase current generates electromagnetic torque to drive the rotor to rotate, and the cooling water circulates in the water inlet area, water tank, and water outlet area of the stator, taking away the heat generated by the rotor's high-speed rotation and air friction and the motor's work, so as to achieve the cooling effect; aluminum water jacket The material is made of aluminum with an oxidized surface, which has light weight, high heat dissipation efficiency, strong corrosion resistance, beautiful appearance, simple and compact structure design, strong rigidity, multiple functions, easy installation and disassembly, and can ensure assembly accuracy. A cooling water tank is added to the connecting seat , can be directly cooled;

10. The machine body waterway is easy to process and has high processing efficiency;

11. A sealing ring is installed between the bearing seat and the inner sleeve of the bearing. The shaft core generates vibration due to gas turbulence impacting the inner sleeve of the bearing when the internal drive rotates at high speed, and the vibration-damping sealing ring acts as a buffer to reduce the vibration when the spindle rotates. , the effect of reducing vibration is good.

Description of drawings

Fig. 1 is a structural schematic diagram of a main shaft section of the present invention.

Fig. 2 is a schematic diagram of the sectional structure of the knife unloading cylinder of the present invention.

Fig. 3 is a structural schematic diagram of the air inlet hole section of the aluminum water jacket of the present invention.

Fig. 4 is a structural schematic diagram of the aluminum water jacket power connector and air return hole of the present invention.

Fig. 5 is a structural schematic diagram of the section of the return hole of the aluminum water jacket of the present invention.

Fig. 6 is a structural schematic diagram of the cross-section of the water inlet hole of the aluminum water jacket of the present invention.

Fig. 7 is a schematic cross-sectional structure diagram of the stator and its water-cooling mechanism of the present invention.

Fig. 8 is a schematic perspective view of the stator and its water-cooling mechanism of the present invention.

Fig. 9 is a schematic cross-sectional structure diagram of the lower air bearing assembly of the present invention.

Fig. 10 is a schematic diagram of the sectional structure of the chuck attachment of the present invention.

Fig. 11 is a schematic diagram of the assembly structure of the main body of the shaft hub and the jacket of the main body of the shaft hub in the chuck attachment of the present invention.

Fig. 12 is a schematic diagram of the structure of the main body K of the shaft hub in the chuck attachment of the present invention.

Detailed ways

Example 1

According to each figure shown in Fig. 1 to Fig. 12, the present invention is provided with gap isolation on the radial periphery of the existing body assembly 10, the cylinder return spring 2, the upper air bearing 4, the shaft core 5, and the flange of the shaft core 5 On the basis of the thrust bearing 9 fixed on the upper surface of the plate 8 and the gap isolation plate 8, the present invention is particularly that the lower air bearing seat assembly 7 is fixed on the thrust bearing 9, and the upper part of the lower air bearing seat assembly 7 is provided with a stator 6 and a shaft core 5 The front end of the body is provided with a chuck attachment 11, the upper opening of the body assembly 10 is fixed with an aluminum water jacket assembly 3, and the upper part of the aluminum water jacket assembly 3 is fixed with a tool change cylinder assembly 1; the upper air bearing 4 is provided with an upper air bearing in the middle of the shaft body Cooling channel 12.

Example 2

Same as Embodiment 1, except that the lower air bearing seat assembly 7 includes a bearing seat 7.2, a radial outer water channel 7.7 on the middle side of the bearing boss of the bearing seat 7.2, and the outer water channel 7.7 near the bearing boss. Water and air seal rings 7.3 are provided on the upper and lower outer walls, and air seal rings 7.6 are provided around the bearing boss. Radial air passages 7.4 are provided near the head end of the bearing boss and near the bearing seat 7.2. The inner wall of the hole is provided with an inner bearing sleeve 7.1, and the head-to-tail connection between the inner bearing sleeve 7.1 and the inner wall of the through hole is provided with a vibration-damping sealing ring 7.5, and the middle part of the inner bearing sleeve 7.1 is provided with an inner water flow channel 7.8 and an outer water flow channel 7.7 In the same way, the inner bearing sleeve 7.1 is provided with an airflow outlet corresponding to the airflow passage 7.4 of the bearing boss, and a damping plug 7.9 is arranged at the airflow outlet.

Example 3

Same as Embodiment 1, except that the stator 6 is provided with a water-cooling mechanism, which includes a power cord 6.5, a water tank 6.3 is provided on the outer wall of the stator 6, and a front sealing ring 6.2 and a rear sealing ring are respectively provided at both ends of the water tank 6.3 6.4 and the water tank 6.3 are evenly divided into a water outlet area 6.7 and a water inlet area 6.6, and a water inlet and return isolation block 6.8 is provided between the water outlet area 6.7 and the water inlet area 6.6.

Example 4

Same as embodiment 1, except that the aluminum water jacket assembly 3 includes the connecting seat 3.2 of the aluminum water jacket, the upper port of the connecting seat 3.2 and the outer wall near the bearing seat are provided with a sealing ring 3.1, and the connecting seat 3.2 is positive The middle part is provided with an axially penetrating push rod hole, the outer wall of the connection seat 3.2 between the two sealing rings 3.1 is provided with a cooling water tank 3.4, and the side wall of the connection seat 3.1 is provided with a water inlet hole 3.9 communicating with the cooling water tank 3.4; The inner wall of the push rod hole is provided with at least one bearing bush 3.3; the air inlet hole 3.5 and the water return hole 3.8 are respectively arranged on the side wall of the connection seat 3.2, both of which are connected with the bottom end surface of the connection seat 3.2; The side wall is provided with an air return hole 3.7 and a power connector 3.6, which are all connected to the inner cavity of the bearing seat, and the upper and lower ends of the inner wall of the push rod hole are provided with bearing bushes 3.3.

Example 5

Same as Embodiment 1, except that the tool change cylinder assembly 1 includes a cylinder body 1.4, the middle and lower parts of the outer wall of the cylinder body 1.4 are provided with exhaust holes, an air intake nozzle 1.1, an upper baffle 1.6, and a lower baffle 1.10 1.7, a top cover 1.3, one or more pistons 1.9 are arranged between each partition and the inner wall of the cylinder body 1.4. The outer wall of the head end is provided with a sealing ring 1.11, the head end of the piston 1.9 is provided with an axial through hole gap 1.13, a sealing ring 1.8 is provided between the piston 1.9 and the inner wall of the cylinder body 1.4, and a through hole 1.14 is provided at the axial center of the piston 1.9, The top inner wall of the through hole 1.14 is provided with a thread 1.16, and a retaining spring 1.5 is provided between the inner wall of the top cover 1.3 and the upper surface of the upper partition 1.6, and a screw 1.2 runs through the top cover 1.3, the upper partition 1.6 and the retaining spring 1.5; the cylinder body 1.4 There are upper-level piston and lower-level piston inside, and the head end gap of the upper-level piston is set at the end of the axial through hole of the lower-level piston; the bottom of the cylinder body 1.4 is provided with a counterbore 1.12 to be fixed with the lower-level cylinder or the body; the middle part of the outer wall of the cylinder body 1.4 is provided with Exhaust hole 1.17, the lower part of the outer wall of the cylinder body 1.4 is provided with an exhaust hole 1.15; the head end of the air intake nozzle 1.1 is provided with a damping hole 1.18.

Example 6

Same as any of the above-mentioned embodiments, except that the chuck attachment 11 includes the shaft core 5, the shaft hub main body 11.2, the shaft hub main body jacket 11.3, the butterfly spring 11.4, the collet 11.5, the shaft hub main body jacket 11.3 The outer wall is provided with two lubricating oil grooves 11.6. the

Claims (5)

1. An air-floating high-speed electric spindle, which includes the body assembly (10), the cylinder return spring (2), the upper air bearing (4), the shaft core (5), and the radial direction at the flange of the shaft core (5). A gap isolation plate (8) is arranged on the periphery, and a thrust bearing (9) is fixed on the upper surface of the gap isolation plate (8). The upper part of the component (7) is provided with a stator (6), the front end of the shaft core (5) is provided with a chuck attachment (11), and the upper opening of the body component (10) is fixed with an aluminum water jacket component (3). The tool change cylinder assembly (1) is fixed on the upper part of the assembly (3); the upper air bearing (4) is provided with an upper air bearing cooling channel (12) in the middle of the shaft body; The lower air bearing seat assembly (7) includes the bearing seat (7.2), the radial outer water channel (7.7) on the middle side of the bearing boss of the bearing seat (7.2), and the outer water channel (7.7) near the bearing boss ( The upper and lower outer walls of 7.7) are equipped with water-air sealing rings (7.3), the periphery of the bearing boss is provided with air-sealing rings (7.6), and the near head end of the bearing boss and the place near the bearing seat (7.2) are equipped with radial through-holes. The inner wall of the through hole in the bearing is provided with an inner bearing sleeve (7.1), and the head-to-tail connection between the inner bearing sleeve (7.1) and the inner wall of the through hole is provided with a vibration-damping sealing ring (7.5) , the middle part of the inner bearing sleeve (7.1) is provided with an inner water channel (7.8) communicating with the outer water channel (7.7), and the air channel (7.4) corresponding to the bearing boss of the inner bearing sleeve (7.1) is provided with an air outlet, and the air outlet is provided with With damping plug (7.9). 2. An air-floating high-speed electric spindle according to claim 1, characterized in that the stator (6) is provided with a water-cooling mechanism, which includes a power cord (6.5), and the outer wall of the stator (6) is provided with a water tank (6.3) , the front and rear sealing rings (6.2) and rear sealing rings (6.4) are respectively provided at both ends of the water tank (6.3). The water tank (6.3) is evenly divided into the water outlet area (6.7) and the water inlet area (6.6). ) and the water inlet area (6.6) is provided with a water inlet and return isolation block (6.8). 3. An air-floating high-speed electric spindle according to claim 1, characterized by the aluminum water jacket assembly (3), which includes the connecting seat (3.2) of the aluminum water jacket, the upper port of the connecting seat (3.2) and Sealing rings (3.1) are provided on the outer wall near the bearing seat, an axially penetrating push rod hole is provided in the middle of the connecting seat (3.2), and cooling is provided on the outer wall of the connecting seat (3.2) between the two sealing rings (3.1). The water tank (3.4), the side wall of the connecting seat (3.1) has a water inlet hole (3.9) connected with the cooling water tank (3.4); the inner wall of the push rod hole is provided with at least one bearing bush (3.3); there is an air inlet hole (3.5) and the return hole (3.8) are respectively set on the side wall of the connection seat (3.2), both of which are connected with the bottom end surface of the connection seat (3.2); there is a return air hole ( 3.7) and the power connector (3.6), both communicate with the inner cavity of the bearing seat, and the upper and lower ends of the inner wall of the push rod hole are equipped with bearing bushes (3.3). 4. An air-floating high-speed electric spindle according to claim 1, characterized in that the tool change cylinder assembly (1) includes a cylinder body (1.4), and the middle and lower parts of the outer wall of the cylinder body (1.4) are provided with exhaust gas hole, air intake nozzle (1.1), upper baffle (1.6), lower baffle (1.10), a sealing ring (1.7) is provided between each baffle and the inner wall of the cylinder (1.4), a top cover (1.3), a Or more than one piston (1.9), the front end of the piston (1.9) runs through the lower partition (1.10), the inner wall of the lower partition (1.10) penetrates and the outer wall of the head end of the piston (1.9) is provided with a sealing ring (1.11), the piston The head end of (1.9) is provided with a notch (1.13) for an axial through hole, a sealing ring (1.8) is provided between the piston (1.9) and the inner wall of the cylinder (1.4), and a through hole is provided at the axial center of the piston (1.9) (1.14), the top inner wall of the through hole (1.14) is provided with thread (1.16), and the inner wall of the top cover (1.3) and the upper surface of the upper partition (1.6) are provided with a retaining spring (1.5), and a screw (1.2) runs through it Top cover (1.3), upper baffle (1.6) and circlip (1.5); cylinder body (1.4) is equipped with upper piston and lower piston, the head end gap of the upper piston is set at the end of the axial through hole of the lower piston; A counterbore (1.12) is provided at the bottom of the cylinder body (1.4) to be fixed to the lower cylinder or body; a vent hole (1.17) is provided in the middle of the outer wall of the cylinder body (1.4), and a vent hole (1.17) is provided at the lower part of the outer wall of the cylinder body (1.4). 1.15); the head end of the air intake nozzle (1.1) is provided with a damping hole (1.18). 5. An air-floating high-speed electric spindle according to any one of claims 1 to 4, characterized by the chuck attachment (11), which includes the shaft core (5), the shaft hub main body (11.2), the shaft hub The main body overcoat (11.3), butterfly spring (11.4), collet (11.5), and the outer wall of the shaft bully main body overcoat (11.3) are provided with two lubricating oil grooves (11.6).

Images