Anti-electrocorrosion coreless motor with labyrinth seal structure

Abstract

The utility model discloses an anti-electrocorrosion coreless motor with a labyrinth seal structure, which comprises a columnar motor shaft, a circle of permanent magnet is arranged to wrap the motor shaft, and a layer of copper wire bag is wrapped outside the permanent magnet. An assembly ceramic ball and a deep groove ball bearing with a sealing ring are arranged at one end of the motor shaft, the deep groove ball bearing is attached and fixed to a clamping spring, the clamping spring is fixed in a clamping spring groove of a motor shell, and the motor shell serves as a shell to wrap the whole coreless motor. One end of the motor shaft provided with the deep groove ball bearing is provided with a circle of protruding fixing rib, one end of the fixing rib is attached to the permanent magnet, and the other end of the fixing rib is connected with the deep groove ball bearing.

Description

TECHNICAL FIELD

[0001] The utility model relates to motor field especially relates to a hollow cup motor with labyrinth seal structure. BACKGROUND

[0002] Hollow cup motor is a kind of miniature servo DC motor, it breaks through the rotor structure form of traditional motor on structure. The motor is mainly composed of stator, rotor and commutation system (for brush motor). Among them, the rotor adopts the hollow cup structure without iron core, the shape is similar to water cup, therefore is called "hollow cup motor". This novel rotor structure completely eliminates the electric energy loss caused by eddy current due to iron core. Hollow cup motor is widely used in some occasions with high precision requirements and installation space requirements due to its small size, fast start speed, high speed and simple internal structure, can carry out fast start and stop.

[0003] The application patent with the application publication number CN116667572A discloses a hollow cup motor, which comprises a metal shell, a permanent magnet is fixedly installed on the inner cavity of the metal shell near the left end, a hollow coil is arranged at the right end of the permanent magnet in the metal shell, a main shaft is fixedly installed at the middle of the hollow coil, and an insulating cover is fixedly installed at the right end of the hollow coil. The application utilizes the rotation generated during the working of the device, converts the rotating power into centrifugal force to drive the liquid to flow, and absorbs the radial jumping through the flowing liquid as buffer, so that the radial jumping can be effectively reduced. Since the buffer of the liquid basically does not generate reverse force, the normal rotation of the device is not greatly affected, the problem that the normal rotation of the device is easily affected by the limiting sleeve in the traditional device is effectively avoided, the radial jumping is reduced without affecting the normal rotation of the device, and the application is suitable for popularization and use. UTILITY MODEL CONTENTS

[0004] Many problems are prone to occur in the use of hollow cup motor. The gear box grease is prone to leak and overflow into the bearing, damaging the bearing. Under the working condition of high voltage direct current, the bearing is prone to electric corrosion, resulting in bearing and motor failure. During assembly, the bearing inner ring is prone to overflow during glue assembly, resulting in bearing failure. The assembly of O-ring to prevent the outer ring of the bearing from rotating with the bearing is also difficult.

[0005] To solve the above problems, the utility model provides technical scheme for: a kind of anti-electricity corrosion hollow cup motor with labyrinth seal structure, including cylindrical motor shaft, is equipped with a circle permanent magnet and is wrapped motor shaft, permanent magnet is wrapped with a layer of copper wire package;Motor shaft one end is equipped with assembly ceramic ball, deep groove ball bearing with sealing ring, deep groove ball bearing is fixedly attached with snap spring, snap spring is fixed in the snap spring groove of motor shell, motor shell is wrapped as shell entire hollow cup motor.Motor shaft is equipped with the one end of deep groove ball bearing and is equipped with a circle protruding fixed rib, fixed rib one end is fixedly attached with permanent magnet, other end is connected with deep groove ball bearing.

[0006] Particularly, fixed rib near permanent magnet side is rear shaft shoulder, near deep groove ball bearing side is front shaft shoulder, motor shaft and deep groove ball bearing connection place is equipped with a circle glue storage groove.Bearing inner ring is assembled by glue, and glue will not cross front shaft shoulder and enter click inside, and will be left in glue storage groove, avoid the problem that bearing inner ring is assembled by too much glue overflow, leading to bearing failure.

[0007] As further improvement of the utility model, deep groove ball bearing internal ball is ceramic ball, bearing outer ring is equipped with several O-rings, bearing axial side wall is equipped with metal gasket, and the side wall of ball cavity of bearing is equipped with sealing ring.Ceramic ball structure deep groove ball bearing effectively solves the problem of electric corrosion of bearing, and improves the service life of bearing and motor.Metal gasket, bearing outer ring and sealing ring form a narrow labyrinth seal structure, so that it is very difficult for gear box grease to enter the sealing ring under the action of centrifugal force in high-speed rotation during the operation of electric tool.Meanwhile, the grease of gear box will splash outward under the action of centrifugal force in high-speed rotation during the operation of electric tool, and will not be in static accumulation state, so it is more difficult for gear box grease to enter the surface of sealing ring, thereby solving the problem of gear box grease leakage and damage to bearing.

[0008] Preferably, the snap spring is a ring structure with no ears and an opening, and the opening is provided with an inclined angle.The snap spring is fixed in the snap spring groove of the motor shell, and one side is fixedly attached with the deep groove ball bearing.The snap spring is designed without ears to avoid interference between the snap spring and the metal gasket of the deep groove ball bearing, and the opening of the snap spring is provided with a detachable inclined angle to facilitate assembly and disassembly of the motor.

[0009] Preferably, the O-rings on the bearing outer ring are fixedly attached with the motor shell.By assembling the O-rings on the bearing outer ring, the bearing outer ring can be prevented from rotating with the motor shaft, and the deep groove ball bearing and the motor shell can be easily assembled without the need to assemble the O-rings into the narrow groove inside the motor shell, which also plays a good sealing role.

[0010] Preferably, the inner diameter of the circlip is larger than the outer diameter of the metal washer, and is between the inner and outer diameters of the bearing outer ring, the circlip directly contacts the deep groove ball bearing body, and does not contact the metal washer. The deep groove ball bearing is pressed to the end face of the circlip under the action of the bearing pre-tightening force, the inner diameter of the circlip is larger than the outer diameter of the metal washer, which ensures that the sealing structure of the deep groove ball bearing does not interfere, and the inner diameter of the circlip is between the inner and outer diameters of the bearing outer ring, so that the circlip is pressed on the end face of the bearing outer ring, that is, the axial position of the deep groove ball bearing is ensured, and interference with the sealing ring is avoided.

[0011] The utility model discloses a beneficial effect is: use the deep groove ball bearing with the labyrinth seal structure on hollow cup motor not only plays good sealing oil -proof effect, and makes the whole motor structure is compact. The deep groove ball bearing of ceramic ball structure effectively solves the electric corrosion problem of bearing, improves the life of bearing and motor. Adopting the earless front circlip structure design on hollow cup motor, not only avoids the interference with bearing sealing structure, and facilitates the disassembly of motor. Through the glue storage groove feature on the motor shaft, not only solves the problem of glue overflow when pressing, and pressing and ensures the effect of gluing. By assembling the double fluorine rubber O type ring on the bearing outer ring, not only solve the problem of O type ring missing and assembling not in place, prevent the outer ring from slipping and stop rotating, also play a good sealing effect. DRAWINGS

[0012] Figure 1 It is the overall sectional view of the utility model.

[0013] Figure 2 It is the sectional view of the deep groove ball bearing of the utility model.

[0014] Figure 3 It is the local sectional view of the motor shaft of the utility model.

[0015] In the drawing, 1-circlip, 2-deep groove ball bearing, 3-motor shaft, 4-motor shell, 5-permanent magnet, 6-copper wire package, 7-O type ring, 8-bearing inner ring, 9-bearing outer ring, 10-metal washer, 11-ceramic ball, 12-sealing ring, 13-glue storage groove, 14-front shaft shoulder, 15-rear shaft shoulder. PREFERRED EMBODIMENT

[0016] Embodiment one: a kind of hollow cup motor with labyrinth seal structure of anti electric corrosion, including cylindrical motor shaft 3, is equipped with a circle permanent magnet 5 and is wrapped motor shaft 3, and permanent magnet 5 is wrapped with a layer of copper wire package 6;Motor shaft 3 one end is equipped with deep groove ball bearing 2, and deep groove ball bearing 2 is fixed with circlip 1, and circlip 1 is fixed in the circlip 1 slot of motor shell 4, and motor shell 4 is wrapped as shell entire hollow cup motor. Motor shaft 3 is equipped with a circle protruding fixed rib on the one end of deep groove ball bearing 2, and the one end of fixed rib is fixed with permanent magnet 5, and the other end is connected with deep groove ball bearing 2.

[0017] Hollow cup motor is a kind of miniature servo DC motor, which breaks through the rotor structure form of traditional motor in structure. The motor mainly consists of a stator, a rotor and a commutation system (for brush motor). Among them, the rotor adopts a hollow cup structure without iron core, which is similar to a water cup, so it is called "hollow cup motor". This novel rotor structure completely eliminates the electric energy loss caused by eddy current due to the iron core. Hollow cup motor has small size, fast starting speed, high speed and simple internal structure, so it can be started and stopped quickly and is widely used in some occasions with high precision requirements and space requirements.

[0018] Among them, the bearing plays a crucial role in the motor, not only can support the rotation of the shaft, ensure the stable rotation of the motor rotor assembly, reduce friction and wear, improve the overall performance and efficiency of the motor, but also can bear radial load and axial load, ensure the stable operation of the motor under various working conditions. The electric corrosion of the bearing refers to the spark generated by the thin lubricating oil film when the current flows in the contact part of the bearing raceway wheel and the rolling body in rotation, which causes local melting and concave-convex phenomenon on the surface.

[0019] The grease leakage of the gear box and the overflow of the glue into the bearing during the assembly of the bearing inner ring with glue are the main reasons for the failure of the bearing in the motor. In order to solve this problem, the current mainstream hollow cup motor mainly focuses on the sealing of the bearing itself, and improves the anti-grease intrusion performance of the bearing itself by changing the material of the lip and the sealing ring. The O-ring 7 in the current mainstream hollow cup motor to prevent the rotation of the bearing outer ring needs to be assembled in the assembly groove of the motor shell with small space. The current hollow cup motor bearing adopts a steel ball structure, which cannot resist the electric corrosion phenomenon generated in the electromagnetic working environment.

[0020] The current method of changing the material of the lip and the sealing ring to improve the anti-grease intrusion performance of the bearing itself cannot completely prevent the grease from entering the bearing, cannot completely solve the problem of grease leakage, and the use of high-performance sealing ring will lead to high cost of the motor. At the same time, this hollow cup motor is prone to noise and shortens the service life after the grease enters the bearing. When the bearing inner ring is assembled with too much glue, the glue will overflow into the bearing, which will cause the bearing to fail prematurely. The O-ring 7 to prevent the rotation of the bearing outer ring is difficult to be inserted into the groove of the motor shell with small space, which leads to the problem of missing or misassembly of the O-ring, and further assembly of the bearing, which leads to the failure of the bearing and the motor. The bearing adopts a steel ball structure, which will inevitably cause electric corrosion phenomenon in the electromagnetic working environment.

[0021] In view of these shortcomings, the embodiment solves the problem of oil leakage of the gear box of the electric tool by adopting the deep groove ball bearing 2 with a labyrinth sealing structure; solves the problem of glue overflow during press fitting by adding a glue storage groove 13 feature on the motor shaft 3; solves the problem of missing and misassembly of the O-ring 7 by assembling the O-ring 7 on the bearing outer ring 9; solves the problem of electric corrosion of the bearing by using ceramic balls 11 inside the bearing.

[0022] In the embodiment, the fixed rib near the permanent magnet 5 side is the rear shaft shoulder 15, the fixed rib near the deep groove ball bearing 2 side is the front shaft shoulder 14, and the motor shaft 3 is provided with a circle of glue storage groove 13 at the connection position of the motor shaft 3 and the deep groove ball bearing 2. When the bearing inner ring 8 is assembled by glue, the glue will not enter the inside of the click through the front shaft shoulder 14, but will be left in the glue storage groove 13, thereby avoiding the problem of excessive glue overflow during the glue assembly of the bearing inner ring 8, which leads to the failure of the bearing.

[0023] Specifically, the balls inside the deep groove ball bearing 2 are ceramic balls 11, the bearing outer ring 9 is provided with a plurality of O-rings 7, the bearing axial sidewall is provided with a metal gasket 10, and the sidewall of the ball cavity of the bearing is provided with a sealing ring 12. The deep groove ball bearing 2 assembled with the ceramic balls 11 effectively solves the problem of electric corrosion of the bearing by using the chemical stability of the ceramic material, thereby improving the service life of the bearing and the motor. The metal gasket 10, the bearing outer ring 9 and the sealing ring 12 form a narrow labyrinth sealing structure, so that it is very difficult for the oil of the gear box to enter the oil through the sealing ring 12. At the same time, the oil of the gear box will splash outward under the action of the centrifugal force of high-speed rotation during the operation of the electric tool, and will not be in a static accumulation state, so that it is more difficult for the oil of the gear box to enter the surface of the sealing ring 12, thereby solving the problem of oil leakage of the gear box damaging the bearing.

[0024] Specifically, the clamp spring 1 is a ring structure without ears and openings, and the openings are provided with bevel angles. The clamp spring 1 is fixed in the clamp spring 1 groove of the motor shell 4 and is fixed with the deep groove ball bearing 2 on one side. The clamp spring 1 adopts a structure without ears, which avoids the interference between the clamp spring 1 and the metal gasket 10 of the deep groove ball bearing 2. Meanwhile, the clamp spring 1 is provided with a detachable bevel angle at the closing part, which facilitates the assembly and disassembly of the motor.

[0025] Specifically, the O-ring 7 on the bearing outer ring 9 is fixed with the motor shell 4. By assembling the O-ring 7 on the bearing outer ring 9, the bearing outer ring 9 can be prevented from rotating with the motor shaft 3, and the deep groove ball bearing 2 and the motor shell 4 can be easily assembled, without the need to assemble the O-ring 7 into the narrow groove inside the motor shell 4, and the O-ring 7 also plays a good sealing role.

[0026] Embodiment two: an anti-electric corrosion hollow cup motor with a labyrinth seal structure, comprising a cylindrical motor shaft 3, provided with a ring of permanent magnets 5 wrapping the motor shaft 3, and a layer of copper wire wrapping 6 wrapping the permanent magnets 5; one end of the motor shaft 3 is provided with a deep groove ball bearing 2, the deep groove ball bearing 2 is fixedly attached to a clamp spring 1, the clamp spring 1 is fixed in a clamp spring 1 slot of a motor shell 4, and the motor shell 4 serves as an outer shell wrapping the entire hollow cup motor. One end of the motor shaft 3 provided with the deep groove ball bearing 2 is provided with a ring of protruding fixing ribs, one end of the fixing ribs is attached to the permanent magnets 5, and the other end is connected to the deep groove ball bearing 2.

[0027] The hollow cup motor is a kind of miniature servo DC motor, which breaks through the traditional motor rotor structure form in structure. The motor mainly consists of a stator, a rotor and a commutation system (for brush motor). Among them, the rotor adopts a hollow cup structure without iron core, which is similar to a water cup, so it is called "hollow cup motor". This novel rotor structure completely eliminates the electric energy loss caused by eddy current formed by the iron core. The hollow cup motor has the advantages of small size, fast starting speed, high speed, simple internal structure, fast starting and stopping, so it is widely used in some occasions with high precision requirements and space requirements.

[0028] Among them, the bearing plays a crucial role in the motor, not only can support the rotation of the shaft, ensure the stable rotation of the motor rotor assembly, reduce friction and wear, improve the overall performance and efficiency of the motor, but also can bear radial load and axial load, ensure the stable operation of the motor under various working conditions. The electric corrosion of the bearing refers to the spark generated by the thin lubricating oil film when the current flows in the contact part of the bearing raceway wheel and the rolling body in rotation, which causes local melting and concave-convex phenomenon on the surface.

[0029] The leakage of grease in the gear box and the overflow of glue into the bearing during the assembly of the bearing inner ring 8 are the main reasons for the failure of the bearing in the motor. In order to solve this problem, the current mainstream hollow cup motor mainly focuses on the sealing of the bearing itself, and improves the anti-grease invasion performance of the bearing itself by changing the material of the lip and the sealing ring. The O-ring in the current mainstream hollow cup motor to prevent the outer ring of the bearing from rotating needs to be assembled in the assembly slot of the motor shell 4 with small space. The current hollow cup motor bearing on the market adopts a steel ball structure, which cannot resist the electric corrosion phenomenon caused in the electromagnetic working environment.

[0030] The existing method of improving the grease invasion resistance of the bearing itself by changing the material of the lip and the sealing ring can hardly prevent the grease from entering the bearing completely, cannot solve the problem of grease leakage thoroughly, and causes high cost of the motor due to the use of high-performance sealing ring. Meanwhile, the hollow cup motor is prone to noise and short service life after the grease enters the bearing. When the bearing inner ring is assembled with glue, excessive glue overflowed into the bearing will cause the bearing to fail prematurely. The current O-ring for preventing the bearing outer ring from rotating is difficult to be inserted into the slot of the motor housing 4 with a narrow space, resulting in the problems of missing O-ring or improper assembly, and further causing the failure of the bearing and the motor. The bearing adopts a steel ball structure, which will inevitably cause electric corrosion in the electromagnetic working environment.

[0031] To solve these problems, the embodiment adopts a deep groove ball bearing 2 with a labyrinth sealing structure to solve the problem of gear box oil leakage of the electric tool; adds a glue storage groove 13 feature to the motor shaft 3 to solve the problem of glue overflow during press fitting; assembles the O-ring 7 on the bearing outer ring 9 to solve the problems of missing O-ring 7 and improper assembly; and uses ceramic balls 11 in the bearing to solve the problem of electric corrosion of the bearing.

[0032] In the embodiment, the fixed rib near the permanent magnet 5 is a rear shaft shoulder 15, the fixed rib near the deep groove ball bearing 2 is a front shaft shoulder 14, and a circle of glue storage grooves 13 is arranged at the connection between the motor shaft 3 and the deep groove ball bearing 2. When the bearing inner ring 8 is assembled with glue, the glue will not enter the bearing inner ring 8, but will be left in the glue storage groove 13, avoiding the problem of excessive glue overflow during the assembly of the bearing inner ring 8 with glue, which causes the failure of the bearing.

[0033] Specifically, the balls in the deep groove ball bearing 2 are ceramic balls 11, the bearing outer ring 9 is provided with a plurality of O-rings 7, the bearing axial sidewall is provided with a metal gasket 10, and the sidewall of the ball cavity of the bearing is provided with a sealing ring 12. In the embodiment, the O-ring 7 is made of double fluorine rubber material to ensure the sealing property and sufficient friction force to the motor housing 4. The deep groove ball bearing 2 with ceramic balls 11 effectively solves the problem of electric corrosion of the bearing and improves the service life of the bearing and the motor. The metal gasket 10, the bearing outer ring 9, and the sealing ring 12 form a labyrinth sealing structure with a narrow space, making it very difficult for the gear box grease to enter the sealing ring 12. Meanwhile, the gear box grease will splash outward under the action of high-speed centrifugal force during the operation of the electric tool, and will not be in a static accumulation state, so it is more difficult for the gear box grease to enter the surface of the sealing ring 12, thereby solving the problem of gear box grease leakage damaging the bearing.

[0034] Specifically, the clamping spring 1 is a ring structure without ear opening, and the opening is provided with an inclined angle. The clamping spring 1 is fixed in the clamping spring 1 groove of the motor shell 4, and is fixed on one side with the deep groove ball bearing 2. The clamping spring 1 adopts a structure without ear, which avoids the interference between the clamping spring 1 and the metal gasket 10 of the deep groove ball bearing 2. Meanwhile, the clamping spring 1 is provided with a detachable inclined angle at the closing opening, which facilitates the assembly and disassembly of the motor.

[0035] Specifically, the O-shaped ring 7 on the bearing outer ring 9 is fixed with the motor shell 4. By assembling the O-shaped ring 7 on the bearing outer ring 9, the bearing outer ring 9 can be prevented from rotating with the motor shaft 3, and the deep groove ball bearing 2 and the motor shell 4 can be easily assembled without the need to assemble the O-shaped ring 7 into the narrow groove inside the motor shell 4, and the O-shaped ring 7 also plays a good sealing role.

[0036] Specifically, in the embodiment, the inner diameter of the clamping spring 1 is greater than the outer diameter of the metal gasket 10 and is between the inner and outer diameters of the bearing outer ring 9. The clamping spring 1 directly abuts with the main body of the deep groove ball bearing 2 and does not contact the metal gasket 10. The deep groove ball bearing 2 is pressed to the end face of the clamping spring 1 under the action of the bearing pre-tightening force. The inner diameter of the clamping spring 1 is greater than the outer diameter of the metal gasket 10, which ensures that the sealing structure of the deep groove ball bearing 2 does not interfere. The inner diameter of the clamping spring 1 is between the inner and outer diameters of the bearing outer ring 9, so that the clamping spring 1 is pressed on the end face of the bearing outer ring 9, which ensures the axial positioning of the deep groove ball bearing 2 and avoids interference with the sealing ring 12.

[0037] The above specific embodiments are only the preferred embodiments of the utility model, and do not limit the specific implementation structure and implementation range of the utility model. In fact, some equivalent changes can be made according to the shape, structure and design purpose of the utility model. Therefore, any equivalent changes made according to the shape, structure and design purpose of the utility model should be included in the protection scope of the utility model, that is, these equivalent changes should be protected by the utility model.

Claims

1. A ferro-corrosion-proof hollow cup motor with a labyrinth seal structure, characterized in that, The motor shaft is provided with a ring of permanent magnets, and the permanent magnets are wrapped with a layer of copper wire; one end of the motor shaft is provided with a ceramic ball, a deep groove ball bearing with a sealing ring, and the deep groove ball bearing is fixedly connected with a clasp spring which is fixed in a clasp spring groove of a motor shell, and the motor shell serves as an outer shell to wrap the entire hollow cup motor.

2. The electrocorrosion resistant hollow cup motor with a labyrinth seal structure according to claim 1, characterized in that, One end of the motor shaft provided with the deep groove ball bearing is provided with a ring of protruding fixing ribs, one end of the fixing ribs is attached to the permanent magnets, and the other end is connected with the deep groove ball bearing.

3. The electrocorrosion-proof hollow cup motor with a labyrinth seal structure according to claim 1 or 2, characterized in that, The side of the fixing ribs close to the permanent magnets is a rear shaft shoulder, and the side close to the deep groove ball bearing is a front shaft shoulder, and the motor shaft is provided with a ring of glue storage grooves at the connection with the deep groove ball bearing.

4. The electrocorrosion resistant hollow cup motor with a labyrinth seal structure according to claim 1, characterized in that, The internal balls of the deep groove ball bearing are ceramic balls, the bearing outer ring is provided with a plurality of O-rings, the bearing axial sidewall is provided with a metal gasket, and the ball cavity sidewall of the bearing is provided with a sealing ring.

5. The electrocorrosion resistant hollow cup motor with a labyrinth seal structure according to claim 1, characterized in that, The clasp spring is a ring structure without ears and with an opening, and the opening is provided with an inclined angle.

6. The electrocorrosion-proof hollow cup motor with a labyrinth seal structure according to claim 1 or 5, characterized in that, The clasp spring is fixed in a clasp spring groove of the motor shell, and one side is attached to and fixed with the deep groove ball bearing.

7. The electrocorrosion resistant hollow cup motor with a labyrinth seal structure according to claim 4, characterized in that, The O-rings on the bearing outer ring are attached to and fixed with the motor shell.

8. The electrocorrosion resistant hollow cup motor with a labyrinth seal structure according to claim 6, characterized in that, The inner diameter of the clasp spring is larger than the outer diameter of the metal gasket, and is between the inner and outer diameters of the bearing outer ring, the clasp spring is directly attached to the deep groove ball bearing body, and does not contact the metal gasket.

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