WO2023245735A1

WO2023245735A1 - Composite motion electric motor having ball bushing, and electric toothbrush

Info

Publication number: WO2023245735A1
Application number: PCT/CN2022/104218
Authority: WO
Inventors: 邱健达
Original assignee: 深圳市一晤未来科技有限公司
Priority date: 2022-06-24
Filing date: 2022-07-06
Publication date: 2023-12-28
Also published as: CN117318426A

Abstract

Provided in the present invention is a composite motion electric motor having a ball bushing. The composite motion electric motor comprises an electric motor shaft; a ball bushing, which is sheathed on the electric motor shaft; an outer ring, which is sheathed on the ball bushing; and a rotation drive portion and a linear drive portion, wherein the ball bushing comprises a retainer and balls, the retainer having several regularly distributed holes, and the balls being nested in the holes; the rotation drive portion comprises a rotation drive portion stator and a rotation drive portion rotor, the rotation drive portion rotor being connected to the electric motor shaft; and the linear drive portion comprises a linear drive portion stator and a linear drive portion rotor, the linear drive portion rotor being connected to the electric motor shaft. By using the characteristic of a ball bushing being able to implement a free movement of an electric motor shaft in an axial direction and a circumferential direction, and under the cooperation and action of a rotation drive portion and a linear drive portion, the present invention realizes a composite motion of the electric motor shaft in a rotation direction and a linear direction.

Description

Composite motion motor and electric toothbrush with ball bushing

This application claims priority to the Chinese patent application with an application date of June 24, 2022, an application number of CN2022107270345, and a name: a composite motion motor with a ball bushing and an electric toothbrush.

Technical field

The invention belongs to the field of electric motors, and in particular relates to a composite motion motor with a ball bushing and an electric toothbrush.

Background technique

In the existing patents for realizing compound motion, the compound motion is generally realized through two independent motors, that is, one independent motor realizes the up and down movement of the motor shaft, and the other independent motor realizes the forward and backward linear movement of the motor shaft. Movement, such as Panasonic's electric toothbrush products; this type of compound movement is not the same as the compound movement patented in this application.

Or please refer to the patent application number "201110420200.9", the invention name is "a moving magnet linear rotation two-degree-of-freedom motor". It is just a theory, simply disclosed by setting up two motors that share a motor shaft, and an electromagnetic drive. One part realizes the left and right rotation of the motor shaft, and the other electromagnetic drive part realizes the forward and backward linear motion of the motor shaft. However, this patent only discloses the design of the electromagnetic drive part and does not mention the design of the structural part at all, so it cannot be truly applied. On the actual product;

Or if there are patents that mention the design of the structural part, please refer to the invention patent with the patent application number "202110858485.8" and the invention title "A two-degree-of-freedom motor for Z-axis and its assembly method". The disclosed structure Part of it is to groove the shaft and fit it through the shaft sleeve. When the shaft moves forward and backward, the sleeve and the shaft are in sliding friction, resulting in large friction loss, low motor efficiency and short service life; and the application number is "201310422927.2", and the invention name is Although the invention patent for "a linear rotating permanent magnet motor" also discloses the structural part, it also only uses simple bearings to support the sliding friction of the shaft. There are also problems such as large friction loss, low motor efficiency, and short service life.

Contents of the invention

In view of the above-mentioned shortcomings of the prior art, the object of the present invention is to provide a compound motion motor with a ball bushing to solve the above-mentioned shortcomings of the background art.

This application proposal provides a motor with an elastic bearing seat, including a motor shaft, a ball bushing sleeved on the motor shaft, an outer ring sleeved on the ball bushing, a rotary drive part, and a linear drive part; The ball bushing includes a cage and balls, the cage has regularly distributed holes, and the balls are nested in the holes; the rotation drive part includes a rotation drive part stator and a rotation drive part rotor, and the rotation drive part includes a stator and a rotor. The drive part rotor is connected to the motor shaft; the linear drive part includes a linear drive part stator and a linear drive part mover, and the linear drive part mover is connected to the motor shaft.

Further, the composite motion motor further includes an inner ring, which is in the shape of a hollow cylinder. The inner ring is arranged on the motor shaft. The balls of the ball bushing are in contact with the inner ring. Roll on the inner ring.

Further, the ball bushing includes a first ball bushing and a second ball bushing, and one of the rotary driving part and the linear driving part is located between the first ball bushing and the second ball bushing. Between the ball bushings or the rotary driving part and the linear driving part are located between the first ball bushing and the second ball bushing.

Further, the rotor of the rotation driving part has a hollow part, and the motor shaft passes through the hollow part.

Further, the rotor of the rotation driving part is a cylindrical magnet with a hollow part.

Further, the linear drive part mover has a hollow part, and the motor shaft passes through the hollow part.

Further, the linear drive part mover includes a mover yoke and a magnetic piece. The magnetic piece is magnetized with 4 poles, and the magnetic poles are N-S-N-S in order.

Further, the linear drive part stator includes a linear stator core, a linear frame and a linear coil. The linear stator core has a tooth portion, and the tooth portion is facing the middle of two adjacent magnetic poles of the magnetic piece; The linear coil is wound on the linear frame, and the linear frame is sleeved on the tooth portion in the middle of the linear stator core.

Further, the magnetic piece includes a first magnetic piece and a second magnetic piece symmetrically arranged with the first magnetic piece.

Further, the linear stator core includes a first linear stator core and a second linear stator core symmetrically arranged with the first linear stator core; the linear coil includes a first linear coil and a second linear stator core symmetrically arranged with the first linear stator core. The first linear coil is symmetrically arranged with the second linear coil.

Further, the compound motion motor with a ball bushing includes a centering elastic component, one end of which is fixed, and the other end is connected to the motor shaft.

Furthermore, the torsional elastic coefficient of the centering elastic component is a specific value, which value can make the corresponding natural frequency of rotational vibration of the motor shaft close to the rotational driving operating frequency.

Furthermore, the linear elastic coefficient of the centering elastic component is a specific value, which can make the corresponding linear vibration natural frequency of the motor shaft close to the linear drive operating frequency.

The present application also provides an electric toothbrush with a composite motion motor having a ball bushing. The electric toothbrush includes the above composite motion motor.

The improvements of this application bring the following advantages:

(1) The embodiment of the present application provides a composite motion motor with a ball bushing. The ball bushing allows relative rotation and relative linear motion between two components. Utilizing the characteristics of the ball bushing and placing it between the motor shaft and the outer ring, with the cooperation and action of the rotary drive part and the linear drive part, the composite motion of the motor shaft's rotational direction and linear motion can be realized; Of course, the movement in the rotational direction and the movement in the linear direction can be performed simultaneously or independently.

(2) Furthermore, the ball bushing realizes the movement of the motor shaft through the relative rolling of the balls and the motor shaft and the relative rolling of the balls and the outer ring. The rolling friction has a very small friction coefficient, so the example of this application greatly reduces Reduces running resistance and improves motor efficiency.

(3) Furthermore, the rotary drive part and the linear drive part are installed in the same motor housing and jointly drive the same motor shaft, simplifying the structural components and reducing the size of the motor.

(4) Further, by optimizing the design of the returning elastic components, the natural frequency of the rotational vibration of the motor shaft is close to the rotational drive working frequency of the motor, and the linear vibration natural frequency of the motor shaft is close to the linear drive working frequency of the motor. Using the system The effects of resonance can increase amplitude or reduce input power.

Description of the drawings

Figure 1 is a schematic structural diagram of a composite motion motor with a ball bushing according to an embodiment of the present invention;

Figure 2 is a schematic cross-sectional view of a composite motion motor with a ball bushing according to an embodiment of the present invention;

Figure 3 is a schematic structural diagram of a cage (excluding balls) according to an embodiment of the present invention;

Figure 4 is a schematic cross-sectional structural diagram of a ball bushing according to an embodiment of the present invention;

Figure 5 is an exploded schematic diagram of a composite motion motor with a ball bushing according to an embodiment of the present invention;

Figure 6 is a schematic structural diagram of the rotation drive part according to the embodiment of the present invention;

Figure 7 is a schematic structural diagram of the stator of the rotation drive part according to the embodiment of the present invention;

Figure 8 is a schematic exploded structural diagram of the linear drive part according to the embodiment of the present invention;

Among them, 1 is the motor shaft, 2 is the ball bushing, 21 is the cage, 22 is the ball, 221 is the hole, 3 is the outer ring, 4 is the rotation drive part, 41 is the rotation drive part stator, 42 is the rotation drive part rotor , 411 is the first stator core, 412 is the first bobbin, 413 is the first coil, 5 is the linear drive part, 51 is the linear drive part stator, 52 is the linear drive part rotor, 511 is the stator core, 5111 is the first linear stator core, 5112 is the second linear stator core, 512 is the linear coil, 5121 is the first linear coil, 5122 is the second linear coil, 513 is the linear frame, and 5131 is the first linear coil. Wire frame, 5132 is the second linear wire frame, 514 is the tooth part, 521 is the mover yoke, 522 is the magnetic piece, 5221 is the first magnetic piece, 5222 is the second magnetic piece, 6 is the motor casing, and 7 is the second magnetic piece. One ball bushing, 8 is the second ball bushing, 9 is the inner ring, and 10 is the returning elastic component.

Detailed ways

The following describes the embodiments of the present invention through specific examples. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments. Various details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

Please refer to Figures 1 to 8. This embodiment provides a composite motion motor with a ball bushing, including a motor shaft 1, a ball bushing 2 sleeved on the motor shaft 1, and a ball bushing 2 sleeved on the motor shaft 1. The outer ring 3 of the sleeve 2 and the rotary drive part 4 and the linear drive part 5; the rotary drive part 4 can drive the motor shaft 1 to achieve rotational motion, and the linear drive part 5 can drive the motor shaft 1 to achieve linear motion; the ball The bushing 2 includes a cage 21 and balls 22. The cage 21 has regularly distributed holes 221, and the balls 22 are nested in the holes 221. In this way, it is ensured that the balls 22 are in contact with the motor shaft 1 The friction between them is rolling friction, which greatly reduces the friction resistance between the motor shaft 1 and the ball bushing 2 during linear motion, which greatly improves the service life and operating efficiency of the motor.

Further, please refer to Figures 6 and 7. The rotation driving part 4 includes a rotation driving part stator 41 and a rotation driving part rotor 42. The rotation driving part rotor 42 is connected to the motor shaft 1; preferably, the rotation driving part The stator 41 is connected to the motor housing 6. Of course, a rotary drive stator 41 can also be directly provided on the motor housing 6, that is, the housing 6 and the rotary drive stator 41 are integrally formed. The rotary drive stator 41 and the rotary drive section The rotor 42 is used to realize the rotation of the motor shaft 3; the linear drive part 5 includes a linear drive part stator 51 and a linear drive part mover 52. The linear drive part mover 52 is connected to the motor shaft 1. Preferably, the linear drive part 52 is connected to the motor shaft 1. The linear drive part stator 51 is connected to the motor housing 6. Of course, it can also be separated from the motor housing 6 and connected separately through the rear end cover or another motor housing. The linear drive part stator 51 and the linear drive part mover 52 are used for Realize the linear motion of the motor shaft 1; in this way, the rotary driving part 4 and the linear driving part 5 can jointly drive the motor shaft 1 to perform a composite motion in the rotation direction and the linear direction.

Among them, please continue to refer to Figure 1. The composite motion motor can be used as the working motor of the electric toothbrush. The rotary driving part 4 of the composite motion motor can drive the motor shaft 3 to rotate clockwise and counterclockwise along the motor shaft at high frequency, thereby producing a circumferential vibration effect. The linear drive part 5 can drive the motor shaft 3 to repeatedly move forward and backward along the motor shaft at high frequency, thereby producing an axial vibration effect. In this way, the motor shaft 3 can drive the toothbrush head to perform compound vibrations in the circumferential and axial directions to achieve all-round cleaning of the teeth.

As an embodiment, please continue to refer to Figure 2. The compound motion motor also includes an inner ring 9. The inner ring 9 is in the shape of a hollow cylinder, that is, a cylindrical shape; preferably, in one embodiment, the inner ring 9 9 can be sleeved on the motor shaft 1, and the balls 22 of the ball bushing 2 are in contact with the inner ring 9 and roll on the inner ring 9, converting the sliding friction between the motor shaft 1 and the bearing into The rolling friction with the ball bushing 2 greatly improves the service life and operating efficiency of the motor. Of course, in another embodiment, the inner ring 9 can also be integrated with the motor shaft 1, that is, the inner ring 9 can also be integrated with the motor shaft 1. One section of the motor shaft 1 serves as the inner ring 9, which can also play the role of the balls 22 rolling on the inner ring 9, ensuring that the motor shaft 1 does not reduce the motion efficiency of the motor shaft 3 when moving linearly.

As an embodiment, please continue to refer to Figures 2, 6 and 8. The ball bushing 2 includes a first ball bushing 7 and a second ball bushing 8. The rotary driving part 4 and the linear driving part One of 5 is located between the first ball bushing 7 and the second ball bushing 8 , that is, the rotation driving part 4 is located between the first ball bushing 7 and the second ball bushing 8 between, or the linear driving part 5 is located between the first ball bushing 7 and the second ball bushing 8 , or both the rotary driving part 4 and the linear driving part 5 are located between the first ball bushing 7 and the second ball bushing 8 . between a ball bushing 7 and the second ball bushing 8. In this embodiment, the rotation driving part 4 is located between the first ball bushing 7 and the second ball bushing 8, so that The motor structure is more compact, effectively reducing the size of the motor.

As an embodiment, please continue to refer to Figures 2, 6 and 7. The rotor 42 of the rotation driving part has a hollow part, and the motor shaft 1 passes through the hollow part. Specifically, the rotor 42 of the rotation driving part is A cylindrical magnet with a hollow portion, the magnet is wrapped and fixedly connected to the motor shaft 1; the rotary drive part stator 41 includes a first wire frame 412, a first stator core 411 and a first coil 413. A bobbin 412 covers the first stator core 411 , and the first coil 413 is wound around the first bobbin 412 . In this embodiment, there are three first coils 413. The three first coils 413 are evenly arranged around the motor shaft 1 in the circumferential direction. When the three first coils 413 are energized, they generate a first magnetic field that changes with time. On the magnet, a torque is generated to rotate the magnet, driving the motor shaft 1 to rotate alternately in forward and reverse directions.

In a specific example, please refer to Figure 5 and Figure 8 , the linear drive part mover 52 has a hollow part, and the motor shaft 1 passes through the hollow part. Specifically, the linear drive part mover 52 It includes a mover yoke 521 and a magnetic piece 522. The magnetic piece 522 is magnetized with 4 poles, and the magnetic poles are N-S-N-S in order; the linear drive part stator 51 includes a linear stator core 511, a linear frame 513 and a linear coil 512. The linear stator core 511 has a tooth portion 514, and the tooth portion 514 is facing the middle of two adjacent magnetic poles of the magnetic piece 522; the linear coil 512 is wound around the linear wire frame 513 to obtain support. The linear wire frame 513 is set on the tooth portion 514 in the middle of the linear stator core 511; the working principle of the linear drive unit 5 is as follows: after the linear coil 512 is energized, a second magnetic field with alternating magnetic poles is formed by changing the direction of the current. , the magnetic piece 522 is affected by the electromagnetic force in the second magnetic field and drives the motor shaft 3 together to move forward or backward along the axial direction.

As another specific example, please refer to Figures 2 and 8. The magnetic piece 522 includes a first magnetic piece 5221 and a second magnetic piece 5222 arranged symmetrically with the first magnetic piece; the linear stator core 511 includes A first linear stator core 5111 and a second linear stator core 5112 arranged symmetrically with the first linear stator core; the linear frame 513 includes a first linear frame 5131 and a second linear stator core 5112 arranged symmetrically with the first linear stator core. The linear coil 5131 is a second linear coil 5132 arranged symmetrically; the linear coil 512 includes a first linear coil 5121 and a second linear coil 5122 arranged symmetrically with the first linear coil.

As an example, please refer to Figure 5. The compound motion motor with a ball bushing also includes a centering elastic component 10. When the motor stops running, the rotating centering elastic component 10 can return the motor shaft 1 to the preset position. the starting position; one end of the centering elastic component 10 is fixed. Specifically, one end of the centering elastic component 10 is fixed to the motor housing or end cover, and the other end is connected to the motor shaft 1. When the motor shaft 1 rotates, it drives the motor shaft 1 1. One end of the connection rotates together, causing the elastic member to deform, so the elastic member gives the motor shaft a centering force to return to the initial position. This centering force constrains the circumferential position of the motor shaft near the preset starting position; the motor When the shaft 1 stops rotating, the centering elastic component 10 drives the motor shaft 1 to return to the starting position through the end connected to the motor shaft 1 .

In a specific example, the torsional elastic coefficient of the returning elastic component 10 is a specific value, and the natural frequency of rotational vibration of the motor shaft 1 corresponding to this value is close to the rotational drive operating frequency. Through the optimized design of the rotating returning elastic component 10 , so that the natural frequency of the rotational vibration of the motor shaft 1 is close to the rotational drive operating frequency of the motor, and the effect of system resonance can be used to increase the amplitude or reduce the input power.

As an embodiment, the linear elastic coefficient of the return-centering elastic component 10 is a specific value, and the linear vibration natural frequency of the motor shaft corresponding to this value is close to the linear drive operating frequency. Through the optimized design of the rotating return-centering elastic component 10, The linear vibration natural frequency of the motor shaft 1 is close to the linear drive operating frequency. The effect of system resonance can be used to increase the amplitude or reduce the input power.

As an embodiment, an electric toothbrush uses the motor in the above embodiment as a working motor.

The above are only preferred specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person familiar with the technical field can easily think of changes or modifications within the technical scope disclosed in the present invention. All substitutions are within the scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims

A composite motion motor with a ball bushing, which is characterized in that it includes a motor shaft, a ball bushing sleeved on the motor shaft, an outer ring sleeved on the ball bushing, a rotary drive part, and a linear drive part. ; The ball bushing includes a cage and balls, the cage has regularly distributed holes, and the balls are nested in the holes; the rotation drive part includes a rotation drive part stator and a rotation drive part rotor, so The rotor of the rotary drive part is connected to the motor shaft; the linear drive part includes a linear drive part stator and a linear drive part mover, and the linear drive part mover is connected to the motor shaft.
A compound motion motor with a ball bushing according to claim 1, characterized in that the compound motion motor further includes an inner ring, the inner ring is in the shape of a hollow cylinder, and the inner ring is disposed on the motor. On the shaft, the balls of the ball bushing contact the inner ring and roll on the inner ring.
A compound motion motor with a ball bushing according to claim 1, characterized in that the ball bushing includes a first ball bushing and a second ball bushing, the rotary drive part and the linear drive One of the two parts is located between the first ball bushing and the second ball bushing, or both the rotary driving part and the linear driving part are located between the first ball bushing and the second ball bushing. between bushings.
A compound motion motor with a ball bushing according to claim 1, characterized in that the rotor of the rotation driving part has a hollow part, and the motor shaft passes through the hollow part.
The compound motion motor with a ball bushing according to claim 1, wherein the rotor of the rotation driving part is a cylindrical magnet with a hollow part.
A compound motion motor with a ball bushing according to claim 1, characterized in that the linear drive part mover has a hollow part, and the motor shaft passes through the hollow part.
A compound motion motor with a ball bushing according to claim 1, characterized in that the linear drive part mover includes a mover yoke and a magnetic piece, and the magnetic piece is 4-pole magnetized, and the magnetic poles are in sequence. For N-S-N-S.
A compound motion motor with a ball bushing according to claim 1, wherein the linear drive part stator includes a linear stator core, a linear frame and a linear coil, and the linear stator core has a tooth portion , the tooth portion is facing the middle of two adjacent magnetic poles of the magnetic piece; the linear coil is wound on the linear wire frame, and the linear wire frame is sleeved on the tooth portion in the middle of the linear stator core.
The compound motion motor with a ball bushing according to claim 7, wherein the magnetic piece includes a first magnetic piece and a second magnetic piece arranged symmetrically with the first magnetic piece.
A compound motion motor with a ball bushing according to claim 8, wherein the linear stator core includes a first linear stator core and a linear stator core symmetrically arranged with the first linear stator core. a second linear stator core; the linear coil includes a first linear coil and a second linear coil arranged symmetrically with the first linear coil.
A compound motion motor with a ball bushing according to claim 1, characterized in that the compound motion motor with a ball bushing includes a centering elastic component, one end of the centering elastic component is fixed, and the other end is connected Motor shaft.
A compound motion motor with a ball bushing according to claim 11, characterized in that the torsional elastic coefficient of the central elastic component is a specific value, which value can make the corresponding natural frequency of the rotational vibration of the motor shaft close to Rotary drive operating frequency.
A compound motion motor with a ball bushing according to claim 11, characterized in that the linear elastic coefficient of the returning elastic component is a specific value, which value can make the corresponding linear vibration natural frequency of the motor shaft close to Linear drive operating frequency.
An electric toothbrush with a ball bushing compound motion motor, characterized by comprising the compound motion motor according to any one of claims 1-13.