Composite motion servo motor

Abstract

The utility model discloses a compound motion servo motor, comprising a housing; the main shaft is arranged in the shell and is sequentially provided with a first position, a second position, a third position and a fourth position in the axial direction; the rotary driving assembly is arranged at a second position of the main shaft and is used for driving the main shaft seat to rotate; the linear driving assembly is arranged at a third position of the main shaft and used for driving the main shaft seat to linearly move; the elastic balance assembly is arranged at the first position and the second position of the main shaft; when the main shaft moves in the axial direction, the elastic balance assemblies at the first position and the fourth position can provide a buffering effect on the movement of the main shaft and enable the rotating shaft to keep balance, the elastic balance assemblies can eliminate collision sound and enable the main shaft to keep balance, and after the movement of the main shaft is buffered by the elastic balance assemblies, the rotating shaft can keep balance. And the shell can be prevented from colliding with the linear driving assembly and the rotary driving assembly, and the service life of the motor is prolonged.

Description

Technical Field

[0001] The utility model relates to the technical field of motors, in particular to a compound motion servo motor. Background Art

[0002] Most of the existing linear rotary motors adopt a split layout. The split linear rotary motor combines a linear motor and a rotary motor through a mechanical structure to simultaneously complete linear and rotary motions in a transmission manner. The internal structure is complex, the volume is large, the mechanical transmission results in low positioning accuracy and slow dynamic response. Essentially composed of two motors, the motors with this layout have a large load and are more difficult to control the positioning accuracy. A compound motion motor is a motor that can achieve linear and rotary motions. It combines the characteristics of a linear motor and a rotary motor. Through a special structural design, it can achieve two motion forms in a single motor. The design of this motor makes it very useful in occasions where linear and rotary motions need to be performed simultaneously, such as in automated production lines, robot arms, precision positioning systems, and electric toothbrushes and other devices.

[0003] Traditional compound motion motors include a linear drive assembly, a rotary drive assembly, and a main shaft. The linear drive assembly is used to drive the main shaft to move linearly, and the rotary drive assembly is used to drive the main shaft to rotate. When the main shaft moves linearly, it will drive the rotary drive assembly and the linear drive assembly to impact the structure of the housing, resulting in a collision sound. And after long-term use, multiple impacts of the main shaft may also cause damage to the linear drive assembly, the rotary drive assembly, and the housing, or the position of the main shaft before and after linear motion does not remain relatively consistent, resulting in uneven front and rear forces and affecting the overall function. Summary of the Utility Model

[0004] In order to overcome the disadvantages that in the prior art, when the main shaft moves linearly, it will drive the rotary drive assembly and the linear drive assembly to impact the structure of the housing, resulting in a collision sound, and after long-term use, multiple impacts of the main shaft may also cause damage to the linear drive assembly, the rotary drive assembly, and the housing, or the position of the main shaft before and after linear motion does not remain relatively consistent, resulting in uneven front and rear forces and affecting the overall function, the utility model provides a compound motion servo motor, including: a housing; a main shaft installed in the housing, with a first position, a second position, a third position, and a fourth position provided in the axial direction in sequence; a rotary drive assembly installed at the second position of the main shaft for driving the main shaft to rotate; a linear drive assembly installed at the third position of the main shaft for driving the main shaft to move linearly; and an elastic balance assembly installed at the first position and the second position of the main shaft.

[0005] Optionally, the rotary drive assembly includes:

[0006] A first stator installed on the periphery of the second position of the main shaft;

[0007] The rotor is fixed at the second position of the main shaft.

[0008] Optionally, the linear drive assembly includes:

[0009] A second stator, installed on the periphery of the third position of the main shaft;

[0010] A mover, fixed at the second position of the main shaft.

[0011] Optionally, the elastic balance assembly includes:

[0012] A fixing member, provided with a through hole, and the main shaft passes through the through hole;

[0013] A connecting member, fixed on the main shaft;

[0014] An elastic member, installed on the main shaft and located between the fixing member and the connecting member, one end of the elastic member is connected to the connecting member, and the other end of the elastic member is connected to the fixing member.

[0015] Optionally, first end caps and second end caps are respectively provided at both ends of the housing, shaft holes are provided on the first end cap and the second end cap, the main shaft sequentially passes through the shaft holes on the first end cap and the second end cap, and the fixing member is installed in the shaft holes of the first end cap and the second end cap.

[0016] Optionally, a wire outlet hole is provided on the second end cap.

[0017] Optionally, a position sensing assembly is further included, and the position sensing assembly is installed on the second end cap.

[0018] Optionally, the position sensing assembly includes a PCB board and a Hall sensor, a magnetic field feedback member is provided at one end of the main shaft, the Hall sensor surrounds the magnetic field feedback member, and the PCB board is electrically connected to the direct drive assembly and the rotary drive assembly.

[0019] Optionally, a groove is provided inside the second end cap, a boss is provided in the groove, and the PCB board is fixed on the boss.

[0020] Optionally, a limiting member is provided on the main shaft, and the magnetic field feedback member is connected to the limiting member.

[0021] The beneficial effects of the present utility model are as follows: An elastic balance component is installed at the first position of the main shaft, then a rotary drive component is installed at the second position of the main shaft, a linear drive component is installed at the third position of the main shaft, and another elastic balance component is continuously installed at the fourth position of the main shaft. The main shaft equipped with the linear drive component, rotary drive component, and elastic balance component is installed in the housing; the rotary drive component drives the main shaft to rotate at the second position, and the linear drive component drives the main shaft to perform a linear motion at the third position. The linear drive component and the rotary drive component realize the composite motion of the main shaft's rotation and linear movement. When the main shaft moves axially, the elastic balance components at the first position and the fourth position will provide a buffering effect for the movement of the main shaft and keep the rotating shaft balanced, avoiding the main shaft from driving the rotary drive component and the linear drive component to impact the housing at too high a speed after being driven by the linear drive component, thereby eliminating the collision sound. It can also make the main shaft 2 return to the initial position after stopping the movement, so as to maintain the balance before being stressed. After the movement of the main shaft is buffered by the elastic balance component, it can also prevent the housing from colliding with the linear drive component and the rotary drive component, and improve the service life of the motor. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The present utility model will be further described below in conjunction with the drawings and embodiments.

[0023] Figure 1 is an assembly schematic diagram in some embodiments;

[0024] Figure 2 is an exploded Figure 1 ;

[0025] Figure 3 is an exploded Figure 2 ;

[0026] Figure 4 is Figure 3 a partial enlarged view of part A in

[0027] Figure 5 is a cross-sectional view in some embodiments;

[0028] Figure 6 is Figure 5 a partial enlarged view of part B in

[0029] Figure 7 is a structural schematic diagram of the second end cover in some embodiments.

[0030] Description of the reference numerals: 1, housing; 2, main shaft; 3, rotary drive assembly; 4, linear drive assembly; 5, elastic balance assembly; 301, first stator bracket; 302, first magnet; 303, rotor bracket; 401, second stator bracket; 402, second magnet; 403, fixing bracket; 501, fixing member; 502, connecting member; 503, elastic member; 101, first end cover; 102, second end cover; 103, wire outlet hole; 104, boss; 6, position sensing assembly; 601, PCB board; 602, Hall sensor; 603, magnetic field feedback member; 604, limiting member. Detailed implementation manners

[0031] The concept, specific structure and technical effects of the present utility model will be clearly and completely described below in conjunction with the embodiments and the drawings, so as to fully understand the purpose, features and effects of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments. Based on the embodiments of the present utility model, other embodiments obtained by those skilled in the art without creative efforts shall fall within the protection scope of the present utility model. In addition, all the connection / connection relationships involved in the patent do not simply refer to the direct connection of components, but refer to the more optimal connection structure that can be formed by adding or reducing connection accessories according to the specific implementation situation. Each technical feature in the creation of the present utility model can be combined interactively without conflicting with each other.

[0032] The present utility model provides an embodiment: a compound motion servo motor, comprising: a housing 1; a main shaft 2, installed in the housing 1, and successively provided with a first position, a second position, a third position and a fourth position in the axial direction; a rotary drive assembly 3, installed at the second position of the main shaft 2; a linear drive assembly 4, installed at the third position of the main shaft 2; and an elastic balance assembly 5, installed at the first position and the second position of the main shaft 2. Among them, the housing 1 is used to protect the main shaft 2 and the components installed on the main shaft 2. The main shaft 2, as the main power output component, is used to connect with external equipment to drive the external equipment. The rotary drive assembly 3 is used to drive the main shaft 2 to rotate, and the linear drive assembly 4 is used to drive the main shaft 2 to move linearly.

[0033] During implementation, an elastic balance assembly 5 is installed at the first position of the main shaft 2, then a rotary drive assembly 3 is installed at the second position of the main shaft 2, a linear drive assembly 4 is installed at the third position of the main shaft 2, and another elastic balance assembly 5 is continuously installed at the fourth position of the main shaft 2. The main shaft 2 equipped with the linear drive assembly 4, rotary drive assembly 3, and elastic balance assembly 5 is installed in the housing 1; the rotary drive assembly 3 drives the main shaft 2 to rotate at the second position, and the linear drive assembly 4 drives the main shaft 2 to perform a linear motion at the third position. The linear drive assembly 4 and the rotary drive assembly 3 achieve the combined motion of rotation and linear motion of the main shaft 2, constituting an integrated linear and rotary drive device. When the main shaft 2 moves axially, the elastic balance assemblies 5 at the first position and the fourth position will provide a buffering effect for the motion of the main shaft 2 and keep the rotating shaft balanced, preventing the main shaft 2 from driving the rotary drive assembly 3 and the linear drive assembly 4 to impact the housing 1 at too high a speed after being driven by the linear drive assembly 4, thereby eliminating the collision sound. It can also make the main shaft 2 return to the initial position after stopping the motion, thus maintaining the balance before being stressed. After the motion of the main shaft 2 is buffered by the elastic balance assembly 5, it can also prevent the housing 1 from colliding with the linear drive assembly 4 and the rotary drive assembly 3, improving the service life of the motor.

[0034] In some embodiments, the rotary drive assembly 3 includes: a first stator installed around the second position of the main shaft 2; a rotor fixed at the second position of the main shaft 2.

[0035] During implementation, the first stator is installed around the main shaft 2, and the rotor is installed on the main shaft 2. After the first stator is powered on, a rotating magnetic field is generated. The rotor responds to the rotating magnetic field generated by the first stator, and the rotor drives the main shaft 2 to rotate. The rotation of the main shaft 2 drives the external connection mechanism.

[0036] Specifically, the first stator includes a plurality of first stator cores (not shown in the figure), a first winding (not shown in the figure), and a first stator bracket 301. The first stator bracket 301 is installed on the inner wall of the housing 1. The first stator core and the first winding are both arranged on the first stator bracket 301. The first stator bracket 301 positions the first stator core and the first winding around the main shaft 2. The rotor includes four first magnets 302 and a rotor bracket 303. The first magnets 302 are installed on the rotor bracket 303, and the rotor bracket 303 is installed on the main shaft 2. The four first magnets 302 surround the main shaft 2. When the first winding is energized, a rotating magnetic field is generated. The first magnets 302 are induced by the rotating magnetic field to drive the main shaft 2 to rotate. When the main shaft 2 is driven by the linear drive assembly 4 to perform a linear motion (axial motion), it drives the rotor and the rotor bracket 303 of the rotary drive assembly 3. The rotor and the rotor bracket 303 may collide with the housing 1, but the elastic balance assembly 5 in the first position provides a buffering effect for the main shaft 2 from the second position to the first position. Therefore, the rotor and the rotor bracket 303 will not collide with the housing 1, eliminating the collision sound generated by the rotor and the rotor bracket 303 hitting the housing 1.

[0037] In some embodiments, the linear drive assembly 4 includes: a second stator installed around the third position of the main shaft 2; and a mover fixed to the second position of the main shaft 2.

[0038] During implementation, the second stator is installed around the third position of the main shaft 2, and the mover is installed at the third position of the main shaft 2. When the second stator is energized, a linear magnetic field is generated. The mover is driven by the corresponding linear magnetic field to drive the main shaft 2 to perform a linear motion. The linear motion of the main shaft 2 drives the external structure.

[0039] Specifically, the second stator includes a second stator core (not shown in the figure), a second winding (not shown in the figure), and a second stator bracket 401. The second stator bracket 401 is installed on the housing 1. The second stator core and the second winding are arranged on the second stator bracket 401. The second stator bracket 401 positions the second stator core and the second winding around the third position of the main shaft 2. The mover includes a second magnet 402 and a fixing bracket 403. The fixing clamp is installed on the main shaft 2, and the second magnet 402 is installed on the fixing bracket 403. When the second winding is energized, a linear magnetic field (axial magnetic field) is generated. The second magnet 402 responds to the linear magnetic field to drive the main shaft 2 to move linearly. When the main shaft 2 is driven by the linear drive assembly 4 to perform a linear motion (axial motion), it drives the mover and the fixing bracket 403 in the linear drive assembly 4. The mover and the fixing bracket 403 may collide with the housing 1, but the elastic balance assembly 5 in the fourth position provides a buffering effect for the main shaft 2 during the movement from the third position to the fourth position. Therefore, the mover and the fixing bracket will not collide with the housing 1, thereby eliminating the collision sound generated by the mover and the fixing bracket 403 hitting the housing 1.

[0040] In some embodiments, the elastic balance assembly 5 includes: a fixing member 501 provided with a through hole through which the main shaft 2 passes; a connecting member 502 fixed to the main shaft 2; and an elastic member 503 mounted on the main shaft 2 and located between the fixing member 501 and the connecting member 502. One end of the elastic member 503 is connected to the connecting member 502, and the other end of the elastic member 503 is connected to the fixing member 501. Among them, the fixing member 501 is a stationary component, the connecting member 502 is used to connect the elastic member 503, and the elastic member 503 is a component with elastic properties and mainly provides a buffering effect.

[0041] During implementation, the connecting member 502 is fixed to the main shaft 2, the elastic member 503 is mounted on the main shaft 2 and one end of the elastic member 503 is connected to the connecting member 502, the other end of the elastic member 503 is connected to the fixing member 501, one end of the main shaft 2 passes through the through hole on the fixing member 501, and after the main shaft 2 is driven by the linear drive assembly 4, it moves in a linear direction. When the main shaft 2 moves, the connecting member 502 will approach or move away from the fixing member 501. When approaching, the elastic member 503 between the fixing member 501 and the connecting member 502 will be compressed, thereby buffering the linear movement of the main shaft 2 and preventing the main shaft 2 from directly rushing towards the fixing member 501 too quickly, thus eliminating the collision sound.

[0042] Specifically, the fixing member 501 is a rolling bearing structure with a through hole at the center. The main shaft 2 can rotate within the fixing member 501, and the fixing member 501 also plays a role in supporting and balancing the main shaft 2. The connecting member 502 is a circular ring plate that is fixedly wound around the main shaft 2. The elastic member 503 is a spring that is sleeved on the main shaft 2. One end of the spring is connected to the connecting member 502, and the other end of the spring is connected to the fixing member 501. When the main shaft 2 is not driven, the springs of the elastic balance assembly 5 in the first position and the springs of the elastic balance assembly 5 in the second position are both in a pre-compressed state, so that the main shaft 2 is in balance in a stationary state. When the main shaft 2 moves, the spring will be further compressed, and the spring continuously exerts a restoring force to buffer the main shaft 2. In the absence of the connecting member 502 and the elastic member 503 in the elastic balance assembly 5, what the direct drive assembly and the rotary drive assembly 3 may hit after being driven by the main shaft 2 is the rolling bearing that supports and balances the main shaft 2. However, after setting the connecting member 502 and the elastic member 503 in the elastic balance assembly 5 and connecting the elastic member 503 to the fixing member 501 and the connecting member 502, the direct drive assembly and the rotary drive assembly 3 will not hit the bearing of the fixing member 501. The elastic coefficient of the spring is a specific value, which can enable the spring to overcome the axial force and return to the balanced state after being stressed and then unstressed. The linear motion controls the linear output force through pulse width modulation (PWM), compresses the displacement generated by compressing the spring, and stops after reaching a certain distance when it cannot overcome the elastic force and the axial force, restricting the forward and backward displacement strokes.

[0043] In some cases, the fixing member 501 may also be additionally provided with a fixing structure having a through hole, such as a fixing block. The connecting member 502 may also be a plurality of connecting columns surrounding the main shaft 2, and the spring is connected to the connecting columns. The elastic member 503 may also be a rubber elastic washer or other components made of elastic materials.

[0044] In some embodiments, first end caps 101 and second end caps 102 are respectively provided at both ends of the housing 1. Shaft holes are provided on the first end caps 101 and the second end caps 102. The main shaft 2 sequentially passes through the shaft holes on the first end caps 101 and the second end caps 102, and the fixing member 501 is installed in the shaft holes of the first end caps 101 and the second end caps 102.

[0045] During implementation, the first end caps 101 and the second end caps 102 are respectively provided at both ends of the housing 1. The first end caps 101 and the second end caps 102 are used to enclose the housing 1 to protect the structure inside the housing 1. A fixing member 501 is installed in the bearing of the first end cap 101, and another fixing member 501 is installed in the shaft hole of the second end cap 102. Installing the fixing member 501 in the shaft hole can stabilize the fixing member 501, that is, the first end caps 101 and the second end caps 102 also play a role in stabilizing the fixing member 501.

[0046] Specifically, the housing 1 is a cylindrical structure with openings at both ends. The internal structures composed of the linear drive assembly 4, the rotary drive assembly 3, and the elastic balance assembly 5 on the main shaft 2 are all located inside the housing 1. The first end caps 101 and the second end caps 102 are respectively fixed at the openings at both ends of the housing 1. The first end caps 101, the second end caps 102, and the housing 1 together play a role in protecting the internal structure. Grooves having the same size as the fixing member 501 are provided in the shaft holes of the first end caps 101 and the second end caps 102. The fixing member 501 is installed in the groove, and the through hole on the fixing member 501 communicates with the bearing. One end of the main shaft 2 passing through the first end cap 101 is used to connect to an external device.

[0047] In some embodiments, a wire outlet hole 103 is provided on the second end cap 102.

[0048] During implementation, the linear drive assembly 4 and the rotary drive assembly 3 need to be electrically connected to other structures through wires to drive the main shaft 2. The wire outlet hole 103 left on the second end cap 102 is used for the wires to pass through and be electrically connected to the linear drive assembly 4 and the rotary drive assembly 3.

[0049] In some cases, a wire outlet hole 103 may also be provided on the housing 1.

[0050] In some embodiments, the compound motion servo motor further includes a position sensing assembly 6, and the position sensing assembly 6 is installed on the second end cap 102.

[0051] During implementation, a position sensing component 6 is installed on the second end cover 102. When the main shaft 2 is driven by the linear drive component 4 and the rotary drive component 3, its position will change. The position sensing component 6 senses the position change of the main shaft 2 and transmits the change signal to the host computer, which controls the linear drive component 4 and the rotary drive component 3, thereby controlling the movement of the main shaft 2.

[0052] In some embodiments, the position sensing component 6 includes a PCB board 601 and a Hall sensor 602. A magnetic field feedback part 603 is provided at one end of the main shaft 2. The Hall sensor 602 surrounds the magnetic field feedback part 603. A boss 104 is provided on the second end cover 102, and the PCB board 601 is fixed on the boss 104. The magnetic field feedback part 603 is used to feedback the magnetic field of the position change of the main shaft 2 to the Hall sensor 602.

[0053] During implementation, the PCB board 601 is installed on the boss 104 of the second end cover 102, and the Hall sensor 602 is installed on the PCB board 601. The magnetic field feedback part 603 moves with the main shaft 2. When the main shaft 2 moves or rotates, it drives the magnetic field feedback part 603. Through the magnetic field feedback part 603 and the Hall sensor 602, the real-time detection of the position of the motor main shaft 2 is realized, and through the FOC logic control, the angle and direction of the rotation of the brushless motor can be accurately controlled. The composite motion servo motor provided by the present utility model can be applied to an electric toothbrush. Combining with the actual working conditions, it simulates the human toothbrushing action. By controlling the motor through the above principle, it rotates forward and backward at a set angle, and during high-speed forward and backward rotation, the motor can also generate a high-frequency vibration effect, thereby simulating the human toothbrushing action.

[0054] Specifically, two Hall sensors 602 are provided. The positions of the two Hall sensors 602 intersect positively, that is, the connecting lines of the two Hall sensors 602 and the center of the PCB intersect at 90°. The potential phase difference generated by the interaction between the Hall sensor 602 and the magnetic field feedback part 603 is used to feedback the position signal. The Hall sensor 602 is a pin-type sensor. There is a groove on the second end cover 102, and the boss 104 is arranged in the groove. After the PCB board 601 is installed on the boss 104, the Hall sensor 602 is located in the groove. One end of the main shaft 2 passes through the shaft hole of the second end cover 102 and enters the groove. The magnetic field feedback part 603 at one end of the main shaft 2 is a circular ring-shaped permanent magnet with two-pole sinusoidal magnetization. The magnetic field feedback part 603 is also located in the groove at the same height plane as the Hall sensor 602. Due to the up and down movement of the motor axially, the Hall sensor 602 adopts a pin-type Hall design, and the magnet adopts an outer radial magnetization design, so that the induction of the Hall sensor 602 will not produce errors or failures due to the up and down change of the distance.

[0055] In some cases, the Hall sensors 602 can also be set to four, and the four Hall sensors 602 are arranged orthogonally in pairs on the PCB board 601.

[0056] In some embodiments, a limiting member 604 is provided on the main shaft 2, and the magnetic field feedback member 603 is connected to the limiting member 604.

[0057] During implementation, a limiting member 604 is provided on the main shaft 2, and the magnetic field feedback member 603 is connected to the limiting member 604. The limiting function serves to stabilize the magnetic field feedback member 603.

[0058] Specifically, the magnetic field feedback member 603 is a magnetic coil sleeved on the main shaft 2, and the limiting member 604 is a copper coil also sleeved on the main shaft 2. The copper coil is fixed on the main shaft 2 through interference fit with the main shaft 2, and the magnetic coil and the copper coil are adhered by glue, so that the magnetic coil is fixed on the copper coil.

[0059] The above is a specific description of the preferred embodiments of the present invention, but the present invention is not limited to the above embodiments. Those skilled in the art can make various equivalent deformations or substitutions without departing from the spirit of the present invention, and these equivalent deformations or substitutions are all included in the scope defined by the claims of this application.

Claims

1. A compound motion servo motor, characterized in that: include: case; A main shaft is installed in the housing and is provided with a first position, a second position, a third position, and a fourth position in sequence in the axial direction; A rotation drive assembly is installed at the second position of the main shaft and is used to drive the main shaft seat to rotate; A linear drive assembly is installed at the third position of the spindle and is used to drive the spindle seat to move linearly; The elastic balancing component is installed at the first position and the second position of the main shaft.

2. The compound motion servo motor according to claim 1, characterized in that: The rotary drive assembly comprises: A first stator is mounted on the periphery of the second position of the main shaft; The rotor is fixed at a second position on the main shaft.

3. The compound motion servo motor according to claim 1, characterized in that: The linear drive assembly comprises: A second stator is mounted on the periphery of the third position of the main shaft; The mover is fixed at the second position of the main shaft.

4. The compound motion servo motor according to claim 1, characterized in that: The elastic balancing components include: A fixing member, provided with a through hole, through which the main shaft passes; A connecting piece, fixed on the main shaft; The elastic member is mounted on the main shaft and is located between the fixing member and the connecting member. One end of the elastic member is connected to the connecting member, and the other end of the elastic member is connected to the fixing member.

5. The compound motion servo motor according to claim 4, characterized in that: The two ends of the shell are respectively provided with a first end cover and a second end cover, the first end cover and the second end cover are provided with axial holes, the main shaft passes through the axial holes on the first end cover and the second end cover in sequence, and the fixing member is installed in the axial holes of the first end cover and the second end cover.

6. The compound motion servo motor according to claim 5, characterized in that: The second end cover is provided with a wire outlet hole.

7. The compound motion servo motor according to claim 5, characterized in that: It also includes a position sensor component, which is installed on the second end cover.

8. The compound motion servo motor according to claim 7, characterized in that: The position sensing component includes a PCB board and a Hall sensor. A magnetic field feedback component is provided at one end of the main shaft. The Hall sensor surrounds the magnetic field feedback component. The PCB board is electrically connected to the direct drive component and the rotation drive component.

9. The compound motion servo motor according to claim 8, characterized in that: A groove is provided in the second end cover, a boss is provided in the groove, and the PCB board is fixed on the boss.

10. The compound motion servo motor according to claim 9, characterized in that: A limiting component is arranged on the main shaft, and the magnetic field feedback component is connected to the limiting component.

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