Grinding wheel spindle air curtain sealing device
By adopting a grinding wheel shaft air curtain sealing device with passive sealing and active removal of large-flux air curtain chamber on the grinder electric spindle, the problem of dust and coolant intrusion is solved, multi-stage sealing and rapid removal are achieved, and the electric spindle is extended. Lifespan and improved stability.
Patent Information
- Application Number
- CN202420580042.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-03-25
- Publication Date
- 2024-12-31
- Estimated Expiration
- 2034-03-25
AI Technical Summary
The front end bearing chamber of the grinder electric spindle is susceptible to invasion of dust and coolant, resulting in bearing wear and reduced insulation of the stator coil, affecting the service life and stability of the electric spindle.
The grinding wheel shaft air curtain sealing device adopts passive sealing and active removal of large-flux air curtain chamber. An annular airway is formed through the air curtain cover, the outer ring of the airway and the inner ring of the airway. The compressed air is used to quickly discharge dust and water, combined with the airway. The barrier function of the curtain cover realizes passive protection and active removal.
Effectively prevent dust and water from entering the front bearing chamber of the spindle, extend the life of the sealing device, ensure a stable and reliable working state, and simplify the processing and assembly process.
Smart Images
Figure CN222269911U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the field of electromechanics, in particular to the field of electric spindles for machine tools, and specifically relates to a front end sealing device for a grinding wheel shaft for a grinding machine. Background Art
[0002] Electric spindles are widely used in various types of high-speed and high-precision CNC machine tools. Compared with belt drive, electric spindles work more stably and can achieve rapid speed increase and decrease and accurate stop. A large amount of metal debris and coolant will be generated during the processing of CNC grinders. If these impurities enter the front bearing chamber of the electric spindle, it will accelerate the wear of the bearing. At the same time, the entry of water also has the risk of causing the insulation level of the stator coil to decrease, affecting the service life and stability of the electric spindle. Therefore, the sealing structure of the front bearing chamber of the electric spindle is a key design part of the electric spindle.
[0003] Especially for the seal of the front bearing chamber of the grinding wheel shaft used in the electric spindle of the grinder, since the grinding wheel will produce a lot of dust and coolant mixed with the grinding wheel and metal debris, the use environment of the grinding wheel shaft is more severe. At the same time, the grinding wheel shaft of the grinder is mostly installed horizontally, and coolant and dust are more likely to enter. Therefore, the grinding wheel shaft of the grinder needs a more efficient sealing device. Utility Model Content
[0004] In order to solve the problem that the working environment of the grinding wheel shaft is dusty and water-rich, and the front end of the grinding wheel shaft is easily invaded by dust and water, a grinding wheel shaft air curtain sealing device which adopts passive sealing and active cleaning of a large-flux air curtain chamber is proposed.
[0005] The grinding wheel shaft air curtain sealing device is used in the front end hole of the spindle housing of the grinding wheel shaft or other similar type electric spindles, including a spindle housing, an air curtain cover, an air duct outer ring and an air duct inner ring. The air curtain cover and the air duct outer ring are directly or indirectly fixed to the spindle housing by bolts. The air duct inner ring is installed on the inner side of the air duct outer ring. The air duct outer ring and the air duct inner ring together constitute an annular air duct and are connected to the air interface on the spindle housing through the air duct that passes through the side wall of the air duct outer ring. The annular gap between the front nut and the air duct outer ring is connected to the annular air duct to form an annular air duct opening. The air curtain cover is installed on the outer end of the air duct outer ring to form an air curtain chamber between the two. The annular air duct opening faces the air curtain cover, and there is an exhaust port on one side of the air curtain chamber.
[0006] The center of the airway outer ring is provided with a step hole for tight fitting and press-fitting the airway inner ring, the step of the step hole is used to position the airway inner ring, the airway outer ring has a radial airway hole that passes through the inner and outer walls, the outer side of the airway outer ring is also provided with a sealing ring limiting groove, the edge of the airway outer ring has circumferentially evenly distributed axial bolt holes for connecting and fixing with the main shaft housing and threaded holes for fixing the air curtain cover.
[0007] The airway inner ring is an annular structure, and its outer side has an airway annular groove for cooperating with the airway outer ring to form an annular airway. The outer diameter of the first edge of the airway annular groove is smaller than the outer diameter of the second edge. The annular airway opening is formed between the outer circumferential surface of the first edge and the airway outer ring, and the outer circumferential surface of the second edge is tightly matched with the airway outer ring so as to be sealed and fixed as a whole.
[0008] The air curtain cover is an annular part with a stepped hole in the center, the inner hole of the small diameter section is matched with the clearance of the rotor shaft, one side of the large diameter section of the stepped hole is provided with an exhaust port leading to the radial outside, the internal cavity of the large diameter section is the air curtain chamber, and the annular air duct opening formed by the air duct outer ring and the air duct inner ring is connected to the air curtain chamber.
[0009] An annular gap is provided between the inner circumferential surface of the airway outer ring and the front nut of the main shaft for tightening the front bearing group, and is interconnected with the airway outer ring and the airway inner ring to form an annular airway opening, so that compressed air enters the air curtain room along the annular airway opening.
[0010] When the spindle is working, the compressed air enters the radial airway hole on the side wall of the airway outer ring from the compressed air interface on the side wall of the spindle housing, and then enters the annular airway formed by the cooperation of the airway outer ring and the airway inner ring. The compressed air in the annular airway enters the air curtain chamber through the annular airway opening formed by the cooperation of the airway outer ring and the airway inner ring and the airway outer ring and the front nut, and then is discharged from the spindle housing through the radial opening on one side of the air curtain chamber. Once external dust and water enter the air curtain chamber through the gap between the rotor shaft and the air curtain cover, the high-speed flowing compressed air quickly discharges the dust and water entering the air curtain chamber out of the spindle from the exhaust port on the side. The direct blocking effect of the air curtain cover and the blocking and clearing effect of the high-speed air curtain formed in the air curtain chamber on external dust and water together form a comprehensive protection function of passively preventing dust and water from entering and actively clearing dust and water.
[0011] In summary, the utility model has the following beneficial technical effects:
[0012] The multi-stage sealing method completely blocks dust and water: the combination of passive protection and active removal can effectively prevent external dust and water from entering the main shaft front bearing chamber. Simple, reliable and long service life: the air curtain cover, the air duct outer ring and the air duct inner ring together form the air curtain chamber and the annular air duct. The rotating rotor shaft and the front nut are matched with other stationary parts in a clearance manner without wear. Therefore, the grinding wheel shaft air curtain sealing device proposed by the utility model is stable, reliable and has a long service life. It is easy to process and assemble. BRIEF DESCRIPTION OF THE DRAWINGS
[0013] Figure 1 The utility model is a schematic diagram of the cross-sectional structure of a grinding wheel shaft electric spindle equipped with the grinding wheel shaft air curtain sealing device.
[0014] Figure 2This is an exploded view of the assembly of the grinding wheel shaft air curtain sealing device of the utility model.
[0015] Figure 3 The utility model is a grinding wheel shaft air curtain sealing device Figure 2 Assembly exploded view rotated 90 degrees horizontally.
[0016] In the figure: 1. stator, 2. rotor, 3. cooling channel inner sleeve, 4. rear bearing seat, 5. bearing top ring, 6. encoding gear, 7. spindle rear cover, 8. water outlet joint, 9. rear nut, 10. power cord, 11. water inlet joint, 12. encoder, 13. rotor shaft, 14. air curtain cover, 15. air channel outer ring, 16. front nut, 17. air channel inner ring, 18. spindle housing, 20. bearing, 24. ring shaped air duct opening, 26. cooling water channel, 141. step hole, 142. bolt hole, 143. exhaust port, 144. air curtain chamber, 151. step hole, 152. sealing ring limit groove, 153. bolt hole, 154. threaded hole, 155. step, 156. air duct, 171. first edge, 172. second edge, 173. air duct ring groove, 181. exhaust groove, 182. screw hole, 183. compressed air interface. DETAILED DESCRIPTION
[0017] The technical solution is further described below in conjunction with the accompanying drawings and specific embodiments to help understand the content of the utility model.
[0018] Figure 1 The figure shows a grinding wheel shaft equipped with the grinding wheel shaft air curtain sealing device of the utility model, wherein the grinding wheel shaft comprises a spindle housing 18, a rotor shaft 13 fixed to the spindle housing 18 through two groups of front and rear bearings 20 and freely rotatable, a rotor 2 fixed to the outer circumference of the middle part of the rotor shaft 13, a stator 1 fixed to the inner side of the middle part of the spindle housing 18, a rear bearing cover 4 assembled at the rear end of the spindle housing 18 and having a rear bearing 20 group fixed therein, a bearing top ring 5 assembled to the outer side of the rear bearing of the rotor shaft 13, an encoding gear 6 assembled to the rear of the rotor shaft 13 and tightly assembled to the outer side of the bearing top ring 5, a rear nut 9 assembled to the rear of the rotor shaft 13 for tightening the bearing 20, the bearing top ring 5 and the encoding gear 6, a spindle rear cover 7 assembled to the rear opening of the rear bearing seat, a water outlet joint 8, a water inlet joint 11 and a power line joint 10 assembled on the spindle rear cover 7, and an air curtain sealing device installed in the annular opening between the front end of the spindle housing 18 and the rotor shaft 13.
[0019] The spindle housing 18, the rear bearing seat 4 and the spindle rear cover 7 are provided with cooling water channels 26 for passing cooling water to remove the heat generated by the grinding wheel spindle during operation, thereby ensuring that the operation is carried out at a suitable temperature.
[0020] like Figure 1 and Figure 2As shown, the grinding wheel shaft air curtain sealing device includes an air curtain cover 14, an airway outer ring 15 and an airway inner ring 17. The front end opening of the spindle housing 18 is a step hole, and three axial screw holes 182 for installing and fixing the airway outer ring 15 are evenly distributed on the step ring surface in the hole, so as to use the step to axially locate and assemble the airway positioning ring 15 and the air curtain cover 14. The air curtain cover 14 and the airway outer ring 15 are connected and fixed by three bolts (the bolts are not drawn in the figure), and the airway outer ring 15 is connected and fixed to the spindle housing 18 by three bolts (the bolts are not drawn in the figure). The airway inner ring 17 is tightly fitted and pressed on the inner side of the airway outer ring 15, and there is an annular gap between the inner circumferential surface of the airway outer ring 15 and the front nut 16 for tightening the front bearing group, and the airway outer ring 15 and the airway inner ring 17 form an annular airway opening 24, which is connected and connected, so that the compressed air enters the air curtain chamber 144 along the annular airway opening 24. An exhaust groove 181 cooperating with the air curtain cover 14 is provided on one side of the end surface of the spindle housing, and a compressed air interface 183 penetrating through the side wall is provided on the outer side of the spindle housing 18 .
[0021] like Figure 2 As shown, the center of the airway outer ring 15 has a stepped hole 151 for tightly fitting the airway inner ring 17, the step 155 of the stepped hole 151 is used to position the airway inner ring 17, the airway outer ring 15 has a radial airway 156 that passes through the inner and outer walls, the outer side of the airway outer ring 15 also has a sealing ring limiting groove 152, the edge of the airway outer ring 15 has three circumferentially evenly distributed axial bolt holes 153 for connecting and fixing with the main shaft housing, and the edge of the airway outer ring 15 also has three circumferentially evenly distributed axial threaded holes 154 for connecting and fixing with the air curtain cover 14. The large diameter section of the stepped hole 151 of the airway outer ring 15 is clearance-matched with the outer side of the front nut 16.
[0022] like Figure 1 and Figure 2 As shown, the airway inner ring 17 is an annular structure, and its outer side has an airway annular groove 173 for cooperating with the airway outer ring to form an annular airway, the outer diameter of the first edge 171 of the airway annular groove 173 is smaller than the outer diameter of the second edge 172, and the annular airway opening 24 is formed between the outer circumferential surface of the first edge 171 and the airway outer ring 15, and the outer circumferential surface of the second edge 172 is tightly matched with the airway outer ring 15 so as to be sealed and fixed as a whole, so that an annular annular groove that is connected to the annular airway opening 24 and is larger than the air gap of the airway opening 24 is formed between the airway inner ring 17 and the airway outer ring 15 to form an annular airway for distributing, buffering, and temporarily storing air.
[0023] like Figure 1 and Figure 3As shown, the air curtain cover 14 is an annular part with a stepped hole 141 in the center, the inner hole of the small diameter section is clearance-matched with the rotor shaft 13, one side of the large diameter section of the stepped hole 141 has an exhaust port 143 leading to the radial outside, and its edge has three circumferentially evenly distributed axial bolt holes 142 for connecting and fixing with the air duct outer ring 15, the internal cavity of the large diameter section of the stepped hole 141 is an air curtain chamber 144, and the annular air duct opening 24 formed by the air duct outer ring 15 and the air duct inner ring 17 is communicated with the air curtain chamber 144.
[0024] An annular gap is provided between the inner circumferential surface of the air duct outer ring 15 and the front nut 16 of the main shaft for tightening the front bearing group, which is interconnected with the annular air duct opening 24 formed by the air duct outer ring 15 and the air duct inner ring 17 , so that compressed air enters the air curtain chamber 144 along the annular air duct opening 24 .
[0025] When the spindle is working, compressed air enters through the compressed air interface 183 on the side wall of the spindle housing 18, and then passes through the radial air duct 156 on the side wall of the air duct outer ring 15, and then enters the annular air duct formed by the air duct annular groove 173 of the air duct outer ring 15 and the air duct inner ring 17. Since the flow area of the air duct annular groove 173 is larger than the annular air duct opening 24, the air quickly fills the air duct annular groove 173. The compressed air in the air duct annular groove 173 enters the air curtain chamber 144 through the annular air duct opening 24 formed by the air duct outer ring 15 and the air duct inner ring 17 and the air duct outer ring 15 and the front nut 16, and then is discharged from the spindle housing 18 through the exhaust port 143 on one side of the air curtain chamber 144. Once external dust and water enter the air curtain chamber 144 through the gap between the rotor shaft 13 and the air curtain cover 14, the high-speed flowing compressed air will quickly discharge the dust and water entering the air curtain chamber 144 out of the main shaft from the side exhaust port 143. The direct blocking effect of the air curtain cover 14 and the blocking and clearing effect of the high-speed air curtain formed in the air curtain chamber 144 on external dust and water together form a comprehensive protection function of passively preventing dust and water from entering and actively clearing dust and water. The air curtain cover 14 can block most of the dust and coolant. The positive pressure formed by the compressed air in the air curtain chamber 144 and the outward blowing airflow formed at the exhaust port 143 make it difficult for dust and coolant to enter the air curtain chamber through the exhaust port and the gap between the air curtain cover 14 and the rotor shaft 13. The changes in the ventilation space and flow cross-sectional area of the airway ring groove 173, the annular airway opening 24, the air curtain chamber 144 and the exhaust port 143 cause changes in the flow rate, pressure and flow direction of the compressed air, so that the compressed air has the maximum flow rate at the annular airway opening 24 that needs to be sealed to form an air curtain seal and purge, and forms a negative pressure suction effect in the matching gap between the airway inner ring 17 and the front nut 16. Even if there are debris in the gap, it will be sucked into the annular airway opening and discharged. The annular airway opening is facing the air curtain cover 144, so the dirt needs to change direction many times to enter the annular airway opening, which increases the difficulty. The multiple sealing measures adopted in the present application ensure the sealing of the fitting gap and are easy to process and assemble.
[0026] The above is only an example of the present utility model and cannot be used to limit the scope of the present utility model. All simple equivalent changes and modifications made according to the scope of the utility model patent application and the description content are within the scope covered by the present utility model patent.
Claims
1. A grinding wheel shaft air curtain sealing device, characterized in that: It includes a main shaft housing, an air curtain cover, an air duct outer ring and an air duct inner ring, the air curtain cover and the air duct outer ring are directly or indirectly fixed to the main shaft housing by bolts, the air duct inner ring is installed on the inner side of the air duct outer ring, the air duct outer ring and the air duct inner ring together constitute an annular air duct and are communicated with the air interface on the main shaft housing through the air duct that passes through the side wall of the air duct outer ring, the annular gap between the front nut and the air duct outer ring is communicated with the annular air duct to form an annular air duct opening, the air curtain cover is installed on the outer end of the air duct outer ring and forms an air curtain chamber therebetween, the annular air duct opening faces the air curtain cover, and there is an exhaust port on one side of the air curtain chamber.
2. The grinding wheel spindle air curtain sealing device according to claim 1, characterized in that: The air curtain cover is an annular part with a stepped hole in the center. The inner hole of the small diameter section is matched with the rotor shaft clearance, and the large diameter section forms the air curtain chamber.
3. The grinding wheel shaft air curtain sealing device according to claim 1 or 2, characterized in that: The airway inner ring is an annular structure, and its outer side has an airway annular groove for cooperating with the airway outer ring to form an annular airway. The outer diameter of the first edge of the airway annular groove is smaller than the outer diameter of the second edge. An annular airway opening is formed between the outer circumferential surface of the first edge and the airway outer ring, and the outer circumferential surface of the second edge is tightly matched with the airway outer ring.
4. The grinding wheel shaft air curtain sealing device according to claim 1 or 2, characterized in that: The center of the airway outer ring is provided with a step hole for assembling the airway inner ring, the step of the step hole is used to position the airway inner ring, and one side of the airway outer ring is provided with a radial airway hole that penetrates the inner and outer walls.
5. The grinding wheel spindle air curtain sealing device according to claim 4, characterized in that: The outer side of the airway outer ring is provided with a sealing ring limiting groove.
6. The grinding wheel spindle air curtain sealing device according to claim 4, characterized in that: The outer ring edge of the air passage is provided with an axial bolt hole for connection and fixing.
7. The grinding wheel spindle air curtain sealing device according to claim 1 or 2, characterized in that: The air curtain cover edge is provided with axial bolt holes for fixing.
8. The grinding wheel spindle air curtain sealing device according to claim 1 or 2, characterized in that: An exhaust groove matched with the exhaust port of the air curtain cover is provided on one side of the front opening of the main shaft housing.
9. The grinding wheel spindle air curtain sealing device according to claim 1 or 2, characterized in that: The outer side of the front end of the main shaft housing is provided with a radial compressed air interface which matches and is connected with the airway hole of the airway outer ring.