Vacuum cleaner robot and its powertrain

Abstract

This utility model relates to a vacuum cleaner robot and its powertrain. The powertrain includes a motor (10) and a reducer (50) mounted on an axial end of the motor (10) for reducing the output of the motor (10). The motor (10) includes an inner stator and an outer rotor. The inner stator includes a stator shaft (13), and the outer rotor includes a rotor housing (23) rotatably mounted to the stator shaft (13). The reducer (50) includes a central shaft (53), a sun gear (55), an internal gear ring (59), and a plurality of planet gears (57). The central shaft (53) is coaxially fixedly connected to the stator shaft (13). The sun gear (55) is a hollow structure and can rotate around the central shaft (53); the planet gears (57) surround the sun gear (55) and mesh with both the sun gear (55) and the internal gear ring (59). The coaxial fixed connection of the stator shaft of the motor and the central shaft of the reducer improves the compactness of the structure and the concentricity of the reducer and the motor.

Description

Technical Field

[0001] This utility model relates to a vacuum cleaner robot and its powertrain. Background Technology

[0002] A typical wheel consists of a rim, a tire mounted on the rim, and a powertrain mounted on the rim. The powertrain includes a motor and a reducer, with the reducer's output driving the rim. Users often desire powertrains with higher torque, more compact design, and easier maintenance. Therefore, solutions that address one or more of these issues are urgently needed. Utility Model Content

[0003] One object of this application is to provide a powertrain that integrates a speed reducer to improve the output torque of the motor.

[0004] In a first aspect, this utility model provides a powertrain including a motor and a reducer. The reducer is mounted to one axial end of the motor for reducing the output of the motor. The motor includes an inner stator and an outer rotor. The inner stator includes a stator shaft and a stator core fixedly mounted to the stator shaft. The outer rotor includes a rotor housing rotatably mounted to the stator shaft, a motor housing extending axially from the rotor housing, and a permanent magnet fixed to the inner wall of the motor housing. The reducer includes a central shaft, a sun gear, an internal gear ring, and a plurality of planetary gears. The central shaft is coaxially fixedly connected to the stator shaft. The sun gear has a hollow structure and can rotate around the central shaft. The plurality of planetary gears surround the sun gear and simultaneously mesh with the sun gear and the internal gear ring.

[0005] In one embodiment, the motor further includes an integrated plate mounted to the stator shaft, the integrated plate including a circuit board and components disposed on the circuit board; the integrated plate is housed within a motor housing of the motor; the stator shaft includes a through hole through which the wiring harness of the integrated plate extends to the outside of the motor.

[0006] In one embodiment, the through hole includes an axial through hole and a radial through hole connected in sequence, the wire harness entering the axial through hole through the radial through hole and extending to the outside of the motor through the axial through hole.

[0007] In one embodiment, the motor includes a motor housing, the motor housing including a first core rotatably mounted to the stator shaft and a first end cover extending outward from the first core; The reducer includes a reducer housing, the reducer housing includes a second end cover plate, the second end cover plate and the first end cover plate are respectively located at the two ends of the axial direction of the power assembly; the power assembly also includes an annular housing, the two ends of the annular housing are respectively fixedly connected to the first end cover plate and the second end cover plate.

[0008] In one embodiment, the motor housing further includes a first annular wall extending from the first end cover towards the reducer; the reducer housing further includes a second annular wall extending from the second end cover towards the motor, the second annular wall being a predetermined distance from the first annular wall; the two ends of the annular housing are respectively stacked on the first annular wall and the second annular wall and fixedly connected, thereby being fixedly connected to the first end cover and the second end cover.

[0009] In one embodiment, the reducer includes a planet carrier fixedly connected to the central shaft; a plurality of planet gears are rotatably mounted to the planet carrier and simultaneously mesh with the sun gear and the internal gear ring, the internal gear ring being fixedly connected to the reducer housing so that the reducer housing can rotate under the drive of the motor.

[0010] In one embodiment, the permanent magnet is a ring-shaped Hellbeck array structure, wherein the magnetic field inside the ring-shaped Hellbeck array structure is greater than the magnetic field outside the ring-shaped Hellbeck array structure.

[0011] In one embodiment, the rotor housing includes a base plate rotatably mounted to the center of the stator shaft and extending radially outward from the center; the motor housing extends axially from the base plate to form a cylindrical annular wall, the open end of the cylindrical annular wall facing away from the reducer; the sun gear includes an outwardly extending connecting portion for fixed connection to the rotor housing; the sun gear is fixedly connected to the side of the rotor housing facing away from the motor housing.

[0012] A second aspect of this utility model provides a vacuum cleaner robot, including a power wheel. The power wheel includes a rim, a tire mounted on the outer periphery of the rim, and a power assembly provided in the first aspect of this utility model. The power assembly is directly or indirectly fixed to the rim.

[0013] In this embodiment, a reducer is installed at the output end of the motor. The reducer is a planetary gear system. The stator shaft of the motor and the central shaft of the reducer are coaxially fixed together, which improves the output torque, the compactness of the structure, and the concentricity of the reducer and the motor. Attached Figure Description

[0014] To further illustrate the specific technical details of this case, please refer to the accompanying drawings, in which: Figure 1 A schematic diagram of a powertrain provided in an embodiment of the present invention; Figure 2 and Figure 1 A schematic diagram of the AA cross-section of the powertrain shown; Figure 3 yes Figure 2 A partial enlarged view of the sectional view shown; Figure 4 yes Figure 1 A schematic diagram of the outer rotor and sun gear of the motor in the powertrain shown; Figure 5 yes Figure 1 A schematic diagram of the reduction gear system used in the powertrain shown. Figure 6 This is a schematic diagram of a powertrain provided in another embodiment of the present invention; Figure 7 yes Figure 6 Side view of the powertrain shown; Figure 8 yes Figure 6 A schematic cross-sectional view of the powertrain shown. Figure 9 yes Figure 6 An exploded schematic diagram of the powertrain shown. Figure 10 yes Figure 6 The diagram shown is a schematic view from one perspective after the powertrain has had its annular housing, first end cover, and second end cover removed. Figure 11 yes Figure 9 A schematic diagram of the component from another perspective; Figure 12 This is a schematic diagram of the rotor housing and sun gear from one perspective. Figure 13 yes Figure 12 A schematic diagram of the component from another perspective. Detailed Implementation

[0015] The technical solutions in the embodiments of this utility model will now be described with reference to the accompanying drawings.

[0016] refer to Figure 1 The powertrain 100 provided in one embodiment of this utility model includes a motor 10 and a reducer 50, with the reducer 50 connected to one end of the motor 10. A wiring harness 34 of the powertrain 100 extends from the other end of the motor 10. The wiring harness 34 may include one or more of the following: motor three-phase wires, encoder wires, and Hall effect wires integrated wiring harness. Preferably, the motor 10 is a hub motor, and the powertrain 100 can be mounted to the wheel rim to directly drive the wheel.

[0017] refer to Figure 2 and Figure 3The motor 10 includes a stator shaft 13, a cylindrical motor housing 11 with one open end, an inner stator, and an outer rotor housed within the motor housing 11. The end of the motor housing 11 is rotatably fitted onto the stator shaft 13, with the open end of the motor housing 11 facing the reducer. The outer rotor is rotatable relative to the stator shaft 13. The inner stator is fixed relative to the stator shaft 13 and is at least partially surrounded by the outer rotor. Thus, the inner stator and outer rotor are protected by the motor housing 11, reducing the risk of external contamination and also contributing to improved dustproof and waterproof performance.

[0018] The inner stator includes a stator core 17 fixedly mounted to the stator shaft 13 and a stator winding 19 wound around the stator core 17. The outer rotor includes a rotor base 23, a motor housing 21, and a permanent magnet; the rotor base 23 includes a base plate 27 rotatably mounted to the center portion 25 of the stator shaft 13 and extending radially outward from the center portion 25; the motor housing 21 extends axially from the base plate 27 to form a cylindrical annular wall, the open end of the cylindrical annular wall facing away from the reducer 50; the stator core 17 and the stator winding 19 are at least partially housed within the space formed by the rotor base 23 and the motor housing 21.

[0019] The reducer 50 includes a central shaft 53, a cylindrical reducer housing 51 with one open end, and a reduction gear system housed within the reducer housing 51. The central shaft 53 is coaxially connected to the stator shaft 13. The end of the reducer housing 51 is rotatably fitted onto the central shaft 53. The open end of the reducer housing 51 faces the motor 10 and is fixedly connected to the open end of the motor housing 11. The reduction gear system reduces the output of the motor 10 and drives the reducer housing 51 and the motor housing 11 to rotate.

[0020] One advantage of this structure is its high degree of integration, which improves the compactness of the structure. At the same time, most of the key components of the powertrain 100 are housed within the space formed by the motor housing 11 and the reducer housing 51, protecting them and reducing the risk of external contamination. This also helps improve dustproof and waterproof performance. Furthermore, the motor 10 integrates the reducer 50, which increases the output torque of the motor 10.

[0021] refer to Figures 2 to 4 The reduction gear system includes a sun gear 55, an internal gear ring 59, a planet carrier 56, and a plurality of planet gears 57; the sun gear 55 is fixedly connected to the outer rotor to rotate synchronously with the outer rotor; the planet carrier 56 is fixed relative to the stator shaft 13 or the central shaft 53; the plurality of planet gears 57 are rotatably mounted to the planet carrier 56, and the plurality of planet gears 57 surround the sun gear 55 and simultaneously mesh with the sun gear 55 and the internal gear ring 59; the internal gear ring 59 is fixedly connected to the reducer housing 51.

[0022] The sun gear 55 is a hollow structure that surrounds the stator shaft 13 or the central shaft 53 and can rotate relative to the stator shaft 13. The sun gear 55 includes an outwardly extending connecting portion 55a for fixed connection to the outer rotor. In this embodiment, the connecting portion 55a is fixedly connected to the rotor seat 23 of the outer rotor by an axial fastener 55c.

[0023] Preferably, the planetary carrier 56 and the central shaft 53 form a single piece to improve the concentricity and stability of the structure, and also reduce the number of parts and the workload of assembly processes.

[0024] In this embodiment, the stator shaft 13 and the central shaft 53 are formed separately to facilitate manufacturing and assembly. One of the stator shaft 13 and the central shaft 53 extends partially into the other. For example, the front end of the stator shaft 13 has a reduced outer diameter, and this front end extends into the cavity of the central shaft 53. Preferably, the front end of the stator shaft 13 includes a protrusion 13c, forming a non-circular structure; correspondingly, the cavity of the central shaft 53 has a non-circular structure, thereby preventing relative rotation between the stator shaft 13 and the central shaft 53.

[0025] In this embodiment, the motor housing 11 and the reducer housing 51 are connected together by fasteners, and a seal is used to seal the motor housing 11 and the reducer housing 51. This reduces the risk of external contamination of the powertrain 100 and also helps to improve dustproof and waterproof performance.

[0026] Specifically, the open end of the motor housing 11 includes a first mating surface 11g and a second mating surface 11i, which are spaced apart along the motor axial direction; the open end of the reducer housing 51 includes a third mating surface 11g and a fourth mating surface 11i; the seal includes a first seal 77 and a second seal 78, with the first seal 77 sandwiched between the first mating surface 11g and the third mating surface 51g, and the second seal 78 sandwiched between the second mating surface 11i and the fourth mating surface 51i.

[0027] The motor 10 also includes an oil baffle 74, which is located on the side of the rotor seat 23 near the reducer 50 and blocks the gap between the motor housing 21 and the motor outer casing 11 to prevent the reducer 50 from contaminating the motor 10.

[0028] In this embodiment, the oil baffle 74 is connected to the motor housing 11. Understandably, the oil baffle 74 may also be connected to the rotor seat 23 or to the reducer housing 51.

[0029] In this embodiment, the motor housing 11 includes a first core 11a rotatably mounted to the stator shaft 13, a first end cover 11c extending outward from the first core 11a, and a first annular wall 11e extending from the first end cover 11c toward the reducer 50; the first core 11a is also fitted with a first shaft seal 71. This structure helps reduce the risk of external contamination of the powertrain 100 and also helps improve dustproof and waterproof performance.

[0030] The reducer housing 51 includes a second spool 51a rotatably mounted to the central shaft 53, a second end cover 51c extending outward from the second spool 51a, and a second annular wall 51e extending from the second end cover 51c toward the motor 10; the second spool 51a is also fitted with a second shaft seal 72. This structure helps reduce the risk of external contamination of the powertrain 100 and also helps improve dustproof and waterproof performance. Preferably, the motor housing 11 and the reducer housing 51 are sealed together.

[0031] The motor 10 also includes an integrated plate 33 mounted to the stator shaft 13. The integrated plate 33 includes a circuit board and components disposed on the circuit board. The integrated plate 33 is housed within the motor housing 11. The stator shaft 13 includes a through hole 13a through which the wiring harness of the integrated plate 33 extends to the outside of the motor 10.

[0032] Preferably, the integrated board 33 includes an encoder with an integrated Hall sensor. This encoder is either a photoelectric encoder or a magnetic encoder. The encoder and the Hall sensor are complementary in function. The encoder focuses on accurately measuring position, speed, and angle; the Hall sensor excels in measuring magnetic field strength, torque, and moment. Using them together enables higher precision measurement and control, and more comprehensive acquisition of the motion status information of the mechanical equipment. In the motor control system of the powertrain 100, the encoder can detect the position, speed, and angle of the motor 10, while the Hall sensor can detect information such as the current and magnetic field of the motor 10. The combination of the two enables precise control of the motor, improving its performance and efficiency.

[0033] refer to Figures 6 to 13 In another embodiment of this utility model, the provided powertrain is... Figure 1The main difference in the powertrain shown is that in the powertrain 100 of this embodiment, the stator shaft 13 of the motor 10 and the central shaft 53 of the reducer 50 are integrally formed; the second end cover plate 51c of the reducer 50 is located axially outside the central shaft 53 and is no longer rotatably mounted to the central shaft 53; the first end cover plate 11c and the second end cover plate 51c of the motor are a certain distance apart, and the second annular wall 51e of the second end cover plate 51c extending toward the motor 10 and the second annular wall 11e of the first end cover plate 11c extending toward the reducer 50 are a preset distance apart; the two ends of the annular outer shell 90 are respectively fixedly connected to the first annular wall 11e and the second annular wall 51e by radial screws 92, thereby being fixedly connected to the first end cover plate 11c and the second end cover plate 51c. The annular outer shell 90 serves as a common outer shell for the motor 10 and the reducer 50, or in other words, the annular outer shell 90 serves as part of both the motor outer shell 11 and the reducer outer shell 51. Preferably, the central through hole of the annular housing 90 includes a first segment 91a and a second segment 91b, wherein the inner diameter of the second segment 91b is smaller than the inner diameter of the first segment 91a, so that the annular housing 90 has a thicker dimension at the second segment 91b, thereby having greater strength. The internal gear ring 59 is located on the inner wall of the second segment 91b of the annular housing 90.

[0034] The other structures and configurations of the powertrain in this embodiment are the same as those in the previous embodiment. Figure 1 The powertrains shown have essentially the same structure and construction. Specifically: The powertrain 100 of this embodiment includes a motor 10 and a reducer 50. The reducer 50 is fixedly mounted to one axial end of the motor 10 for reducing the output of the motor 10. The reducer 50 includes a reducer housing 51 and a reduction gear train housed within the reducer housing 51. The reduction gear train includes a sun gear 55, an internal gear ring 59 surrounding the sun gear 55, a plurality of planet gears 57 surrounding the sun gear 55, and a planet carrier 56 for mounting the planet gears 57. The planet carrier 56 does not rotate, and the internal gear ring 59 is fixedly connected to the reducer housing 51, thereby allowing the reducer housing 51 to rotate under the drive of the motor 10.

[0035] The internal gear ring 59 is fixedly connected to the reducer housing 51 as a whole. For example, the outer peripheral surface of the internal gear ring 59 is directly or indirectly fixedly connected to the inner wall of the reducer housing 51, or the axial end face of the internal gear ring 59 is directly or indirectly fixedly connected to the reducer housing 51.

[0036] The motor 10 includes a stator shaft 13 and a motor housing 11. The motor housing 11 includes a first cavity 11a rotatably mounted to the stator shaft 13, a first end cover 11c extending outward from the first cavity 11a, and a first annular wall 11e extending from the first end cover 11c toward the reducer 50. The first annular wall 11e is fixedly connected to the reducer housing 51 via an annular housing 90. A first bearing 12 is mounted on the first cavity 11a, allowing the motor housing 11 to rotate relative to the stator shaft 13. The motor 10 also includes an integrated plate 33 mounted to the stator shaft 13. The integrated plate 33 includes a circuit board and components disposed on the circuit board. The integrated plate 33 is housed within the motor housing 11 of the motor 10. The stator shaft 13 includes a through hole 13a through which the wiring harness 34 of the integrated plate 33 extends to the outside of the motor 10. The through hole 13a includes an axial through hole and a radial through hole connected in sequence. The wire harness 34 enters the axial through hole through the radial through hole and extends to the outside of the motor 10 through the axial through hole.

[0037] The planetary carrier 56 of the reducer 50 is fixed relative to the central shaft 53. A plurality of planetary gears 57 are rotatably mounted to the planetary carrier 56 and simultaneously mesh with the sun gear 55 and the internal gear ring 59. The sun gear 55 is a hollow structure that surrounds the central shaft 53 and is rotatable relative to the central shaft 53. The sun gear 55 includes an outwardly extending connecting portion 55a, which is fixedly connected to the outer rotor of the motor 10. More specifically, the connecting portion 55a is fixed to the rotor seat 23 by axial screws 55. The rotor seat 23 includes a center portion 25 rotatably mounted to the stator shaft 13 and a base plate 27 extending radially outward from the center portion 25. The motor housing 21 extends axially from the base plate 27 to form a cylindrical annular wall, and the permanent magnet 29 is fixedly mounted to the inner wall of the cylindrical annular wall. The central portion 25 forms a bearing housing 26, which also mounts a second bearing 31. The rotor housing 23 is rotatably mounted to the stator shaft 13 or the central shaft 53 via the second bearing 31, allowing the rotor housing 23 to rotate relative to the stator shaft 13. Preferably, the permanent magnet 29 has a ring-shaped Hellbeck array structure. The magnetic field inside the ring-shaped Hellbeck array structure is greater than the magnetic field outside the ring-shaped Hellbeck array structure, thereby generating a stronger magnetic field in the air gap between the inner stator and the outer rotor, significantly reducing the rotational inertia of the outer rotor, and achieving smoother torque transmission.

[0038] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A powertrain comprising an electric motor (10) and a reducer (50), characterized in that: The reducer (50) is mounted on one axial end of the motor (10) to reduce the output of the motor (10); The motor (10) includes an inner stator and an outer rotor; the inner stator includes a stator shaft (13) and a stator core (17) fixedly mounted to the stator shaft (13); the outer rotor includes a rotor seat (23) rotatably mounted to the stator shaft (13), a motor housing (21) extending axially from the rotor seat (23), and a permanent magnet (29) fixed to the inner wall of the motor housing (21); The reducer (50) includes a central shaft (53), a sun gear (55), an internal gear ring (59), and a plurality of planet gears (57); the central shaft (53) is coaxially fixedly connected to the stator shaft (13); the sun gear (55) is a hollow structure and can rotate around the central shaft (53); the plurality of planet gears (57) surround the sun gear (55) and mesh with the sun gear (55) and the internal gear ring (59) at the same time.

2. The powertrain of claim 1, wherein: The stator shaft (13) and the center shaft (53) are integrally formed.

3. The powertrain of claim 1, wherein: The motor (10) also includes an integrated plate (33) mounted to the stator shaft (13), the integrated plate (33) including a circuit board and components disposed on the circuit board; the integrated plate (33) is housed in the motor housing (11) of the motor (10); the stator shaft (13) includes a through hole (13a), and the wiring harness (34) of the integrated plate (33) extends to the outside of the motor (10) through the through hole (13a).

4. The powertrain of claim 3, wherein: The through hole (13a) includes an axial through hole and a radial through hole connected in sequence. The wire harness (34) enters the axial through hole through the radial through hole and extends to the outside of the motor (10) through the axial through hole.

5. The powertrain as described in claim 1, characterized in that: The motor (10) includes a motor housing (11), which includes a first core (11a) rotatably mounted to the stator shaft (13) and a first end cover (11c) extending outward from the first core (11a). The reducer (50) includes a reducer housing (51), the reducer housing (51) includes a second end cover (51c), the second end cover (51c) and the first end cover (11c) are respectively located at the two ends of the axial direction of the powertrain; The powertrain also includes an annular housing (90), the two ends of which are fixedly connected to the first end cover plate (11c) and the second end cover plate (51c), respectively.

6. The powertrain as described in claim 5, characterized in that: The motor housing (11) also includes a first annular wall (11e) extending from the first end cover (11c) toward the reducer (50). The reducer housing (51) also includes a second annular wall (51e) extending from the second end cover (51c) toward the motor (10), the second annular wall (51e) being at a predetermined distance from the first annular wall (11e); The two ends of the annular outer shell (90) are respectively stacked on the first annular wall (11e) and the second annular wall (51e) and fixedly connected, thereby being fixedly connected to the first end cover plate (11c) and the second end cover plate (51c).

7. The powertrain of claim 1, wherein: The reducer (50) includes a planet carrier (56) which is fixedly connected to the central shaft (53); a plurality of planet gears (57) are rotatably mounted to the planet carrier (56) and simultaneously mesh with the sun gear (55) and the internal gear ring (59), the internal gear ring (59) being fixedly connected to the reducer housing (51) so that the reducer housing (51) can rotate under the drive of the motor (10).

8. The powertrain of claim 1, wherein: The permanent magnet has a structure of a ring-shaped Hellbeck array, and the magnetic field inside the ring-shaped Hellbeck array is greater than the magnetic field outside the ring-shaped Hellbeck array.

9. The powertrain as described in claim 1, characterized in that: The rotor housing (23) includes a central portion (25) rotatably mounted to the stator shaft (13) and a base plate (27) extending radially outward from the central portion (25); the motor housing (21) extends axially from the base plate (27) to form a cylindrical annular wall, the open end of the cylindrical annular wall being away from the reducer (50). The sun gear (55) includes an outwardly extending connecting portion for fixed connection to the rotor housing (23); the sun gear (55) is fixedly connected to the side of the rotor housing (23) opposite to the motor housing (21).

10. A robot vacuum cleaner characterized by: The system includes a power steering wheel, which comprises a rim, a tire mounted to the outer periphery of the rim, and a powertrain as described in any one of claims 1 to 9, the powertrain being directly or indirectly attached to the rim.

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