Gear reducer and motor integrated machine

Abstract

To provide a connection shaft and a speed-reducer-and-motor all-in-one machine.SOLUTION: A speed-reducer-and-motor all-in-one machine 1 comprises a connection shaft 10, a motor 20 and a speed reducer 30. The connection shaft has a first section 11 and a second section 12 having different diameters arranged in an axial direction, and comprises an accommodation space 13 in communication between a front end and a rear end of the connection shaft along the axial direction. An elliptical cam is formed on an outer surface of the second section. An outer diameter of the first section is greater than a long-axis length of the elliptical cam. The motor comprises a stator 21, a rotating member 22 spatially corresponding to the stator, and a central shaft 23 penetrating the stator and arranged along the axial direction. An inner surface of the first section is concentrically sleeved on the rotating member of the motor along a radial direction. The central shaft and the stator are accommodated in the accommodation space. The speed reducer comprises a speed reducer output shaft 31 concentrically sleeved on the connection shaft along the radial direction, and connected to the outer surface of the second section through a first bearing.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a power drive device, and particularly to a speed reducer-motor integrated machine that simplifies the assembly structure of a speed reducer and a motor to achieve the purpose of thinning and maintains the characteristics of a high reduction ratio.

Background Art

[0002] A speed reducer combined with a motor (motorized speed reducer) or a geared motor is an integrated power drive device that combines a motor and a speed reducer. When the motor operates at high speed and low torque, the motor speed reducer can convert it to low speed and high torque via the speed reducer, so it can provide high torque output with a relatively small volume. Therefore, it is common in the industry to combine a motor and a speed reducer for use as a power drive device.

[0003] In the configuration of a conventional geared motor, usually, a gear is arranged on the motor rotating shaft to mesh and drive the speed reducer, or the speed reducer is arranged coaxially on one side of the motor rotating shaft. However, when it is necessary to arrange the motor and the speed reducer coaxially, the overall volume of the combination of the two in the front and rear axial directions is huge, and especially the axial length part where the motor rotating shaft and the speed reducer are connected takes up too much space. Therefore, in the arrangement structure of the speed reducer and the motor, how to effectively improve the space utilization rate, maintain a high reduction ratio, and reduce the structural parts and space volume is an important issue in this field.

[0004] Therefore, by integrating the arrangement of the motor and the speed reducer, while maintaining the characteristics of a high reduction ratio, it is necessary to provide a speed reducer-motor integrated machine to improve the problem that it is difficult to reduce the overall volume and achieve thinning in a conventional coaxial motor speed reducer, and to solve the deficiencies of the prior art.

Summary of the Invention

Problems to be Solved by the Invention

[0005] The objective of the present invention is to provide an integrated motor-reducer unit that improves upon the problem that conventional coaxial motor reducers have difficulty reducing overall volume and achieving a thin profile while maintaining high reduction ratio characteristics, by integrating the arrangement of the motor and reducer.

[0006] Another object of the present invention is to provide a gearbox-motor integrated machine. The gearbox and motor are combined by an integrated connecting shaft, which has a first section and a second section with different diameters arranged in the axial direction, forming different housing spaces. Furthermore, the outer rotor motor and gearbox are fitted concentrically along the radial direction to form parallel axes, and the connecting shaft is positioned radially midway between the outer rotor motor and the gearbox input shaft, which helps optimize space. In addition, the integrally formed connecting shaft simultaneously provides the functions of the output shaft of the outer rotor motor and the input shaft of the gearbox, with the large-diameter first section constituting, for example, the output shaft of the outer rotor motor, and the small-diameter second section constituting, for example, the input shaft of the gearbox, which helps simplify the connection between the output shaft of the outer rotor motor and the input shaft of the gearbox. Two sets of bearings are fitted concentrically along the radial direction via the second section of the connecting shaft, which helps shorten the axial length and achieve a thinner design. Furthermore, the first section, which provides the function of the outer rotor motor output shaft, is circular, and the outer diameter of the first section can be designed according to the required housing space for the motor and the pitch circle diameter (PCD) of the gear meshing in the reducer. The second section, which provides the function of the reducer input shaft, is an elliptical cam, and under the condition that the minor axis length of the elliptical cam does not touch the inner diameter of the second section and does not exceed the outer diameter of the first section, the pitch circle diameter of the gear meshing in the reducer has a design parameter within a specific range for the difference between the major axis length and the minor axis length of the elliptical cam. The motor and reducer combined by the integrated connecting shaft of the present invention maintain the characteristics of a high reduction ratio.

[0007] Another object of the present invention is to provide a gearbox-motor integrated machine. Since independent spaces are provided inside and outside the integrated connecting shaft, the space between the outer wall of the connecting shaft and the gearbox can be used as, for example, an oil reservoir, and the inside of the connecting shaft, as an independent area housing the motor and encoder, is not contaminated by the lubricating oil on the gearbox side. On the other hand, the gearbox-motor integrated machine can be directly connected to a ball spline and slide along the axial direction, enabling the application of high reduction ratios and obtaining higher transmitted torque with better cost advantages. The spline shaft of the ball spline can pass through the central axis of the motor, and the spline nut is directly fixedly connected to the output end of the gearbox to form an integrated structure, which simplifies and compacts the overall structure, improves the utilization rate of space volume, and enables the achievement of high reduction ratios and high transmitted torque. [Means for solving the problem]

[0008] To achieve the above objective, the present invention provides a gearbox-motor integrated machine comprising a connecting shaft, a motor, and a gearbox. The connecting shaft comprises a first section, a second section, and a housing space, the first and second sections being arranged axially, the housing space communicating between the front and rear ends of the connecting shaft along the axial direction, the outer surface of the second section of the connecting shaft forming an elliptical cam, and the outer diameter of the first section being greater than the major axis length of the elliptical cam. The motor is housed in the housing space and connected to the inner surface of the first section. The gearbox is connected to the outer surface of the second section.

[0009] In one embodiment, the motor comprises a stator, a rotating member spatially corresponding to the stator, and a central shaft that penetrates the stator and is positioned axially, wherein the inner surface of a first section of the connecting shaft is concentrically sleeved to the rotating member of the motor radially, together forming the rotor of the motor, and the central shaft and stator are housed within a housing space.

[0010] In one embodiment, the reducer comprises a reducer output shaft connected to the outer surface of a second section of the connecting shaft via a first bearing, and is mounted concentrically on the connecting shaft along the radial direction.

[0011] In one embodiment, the inner surface of the second section of the connecting shaft is fitted concentrically to the central shaft of the motor radially via a second bearing.

[0012] In one embodiment, the reducer output shaft, the first bearing, the second section of the connecting shaft, the second bearing, and the motor's central shaft are arranged radially from the outside to the inside.

[0013] In one embodiment, the gearbox-motor integrated machine further includes an end cap adjacent to the front end of the connecting shaft and fixed to one end of the motor's central shaft.

[0014] In one embodiment, the motor is spatially aligned with the front end of the connecting shaft and further comprises an encoder for measuring information on the rotational speed and angle of the connecting shaft, the encoder being fixed to the end cap or the front end of the connecting shaft.

[0015] In one embodiment, the front end of the connecting shaft is connected to the end cap via a third bearing.

[0016] In one embodiment, the diameter of the first section gradually increases to a constant value along the direction away from the second section.

[0017] In one embodiment, the fixed end of the gearbox is connected to an end cap, and the fixed end, the first section of the connecting shaft, the rotating member of the motor, the stator, and the central shaft are arranged radially from the outside to the inside.

[0018] In one embodiment, the central shaft of the motor extends outward through the front end of the connecting shaft, and the motor is fixed to the outer peripheral edge of the central shaft, housed in a housing space, and includes a circuit board adjacent to the front end of the connecting shaft.

[0019] In one embodiment, the circuit board is externally connected via a motor lead wire, and the motor lead wire is externally connected through the hollow portion of the central axis.

[0020] In one embodiment, the elliptical cam has a major axis length and a minor axis length, and the minor axis length is greater than the inner diameter of the second section and not greater than the outer diameter of the first section.

[0021] In one embodiment, the gear meshing in the speed reducer has a pitch circle diameter that is not less than the outer diameter of the first section.

[0022] In one embodiment, for the pitch circle diameter, a design parameter in the range of 18 to 92 is defined with respect to the difference between the major axis length and the minor axis length.

[0023] In one embodiment, the first section and the second section of the connecting shaft are integrally formed.

[0024] In one embodiment, the connecting shaft forms a motor output shaft connected to the rotating member of the motor through the inner surface of the first section of the connecting shaft. When the motor rotates, the speed reducer is driven through the connecting shaft.

[0025] In one embodiment, the connecting shaft forms a speed reducer input shaft connected to the speed reducer output shaft of the speed reducer through the outer surface of the second section of the connecting shaft and the first bearing. When the motor rotates, the speed reducer is driven through the connecting shaft.

[0026] In one embodiment, the speed reducer-motor integrated machine further includes a ball spline connected to the speed reducer output shaft. The ball spline includes a spline nut, a spline shaft, and a plurality of balls. The spline shaft axially penetrates through the central axis of the motor. The spline nut is concentrically sleeved on the spline shaft along the radial direction and is fixed to the output end of the speed reducer and connected to the spline shaft through the plurality of balls.

[0027] In one embodiment, an oil reservoir is formed between the outer peripheral wall of the speed reducer and the connecting shaft.

Brief Description of the Drawings

[0028] [Figure 1] It is a cross-sectional view of a speed reducer - motor integrated machine of the first preferred embodiment of the present invention. [Figure 2] It shows the three-dimensional structure of the connecting shaft in the speed reducer - motor integrated machine of the first preferred embodiment of the present invention. [Figure 3] It is a rear view of the connecting shaft in the speed reducer - motor integrated machine of the first preferred embodiment of the present invention. [Figure 4] It is a cross-sectional view of the connecting shaft in the speed reducer - motor integrated machine of the first preferred embodiment of the present invention. [Figure 5] It is a cross-sectional view of a speed reducer - motor integrated machine of the second preferred embodiment of the present invention.

Modes for Carrying Out the Invention

[0029] Several typical embodiments illustrating the features and advantages of the present invention will be described in the following description. The present invention can have various variations in different embodiments, all of which will not depart from the scope of the invention, and the description and drawings are essentially illustrative and not intended to limit the invention. For example, where the following descriptions of this disclosure describe placing a first feature above or above a second feature, this indicates that embodiments include those in which the placed first feature is in direct contact with the second feature, and also include those in which an additional feature is placed between the first and second features, thereby preventing the first feature from directly contacting the second feature. Furthermore, overlapping reference numerals and / or symbols may be used in different embodiments of this disclosure. These overlaps are for the purpose of simplification and clarity and are not intended to limit the relationships between each embodiment and / or the aforementioned external structures. Additionally, spatial terms such as "inside," "outside," "front," "back," and similar terms may be used to briefly describe the relationship between components or feature elements in the drawings. In addition to the orientations shown in the drawings, spatial terminology is used to include different orientations of the device in use or operation. The device may be positioned separately (e.g., rotated 90 degrees or positioned in other orientations), and the descriptions of spatial terminology used should be interpreted accordingly. Furthermore, when one component is said to be “connected” or “joined” to another component, it may be directly connected or joined to the other component, or there may be an intervening component. The broad range of numerical values ​​and parameters in this disclosure are approximations, but numerical values ​​are described as accurately as possible in specific examples. Furthermore, terms such as “first,” “second,” and “third” may be used in the claims to describe different components, but these components should not be limited by these terms, and it should be understood that these components described in embodiments are indicated by different component symbols. These terms are for distinguishing different components.For example, the first component may be referred to as the second component, and similarly, the second component may be referred to as the first component, without departing from the scope of the embodiment. The terms “and / or” used in this manner include any or all combinations of one or more enumerated items. Except in the examples of operation / work or unless expressly provided otherwise, all numerical ranges, quantities, values, and percentages disclosed herein (e.g., angles, durations, temperatures, operating conditions, quantity ratios, and similar percentages) should be understood to be modified by the terms “about” or “substantially” in all embodiments. Accordingly, unless otherwise indicated, numerical parameters described in this disclosure and the appended claims are approximations that may be modified as needed. For example, each numerical parameter should be interpreted by applying the usual rounding principles based on the number of significant digits described. In this specification, a range may be expressed as from one endpoint to another, or between two endpoints. All ranges disclosed herein include endpoints unless otherwise specified.

[0030] Figure 1 is a cross-sectional view of a gearbox-motor integrated machine according to a first preferred embodiment of the present invention. Figure 2 shows the three-dimensional structure of the connecting shaft in the gearbox-motor integrated machine according to a first preferred embodiment of the present invention. Figure 3 is a rear view of the connecting shaft in the gearbox-motor integrated machine according to a first preferred embodiment of the present invention. Figure 4 is a cross-sectional view of the connecting shaft in the gearbox-motor integrated machine according to a first preferred embodiment of the present invention. In this embodiment, the gearbox-motor integrated machine (hereinafter simply referred to as the integrated machine) 1 comprises a connecting shaft 10, a motor 20, and a gearbox 30. The motor 20 and the gearbox 30 are connected via the connecting shaft 10 and simultaneously integrated into the integrated machine. In this embodiment, the connecting shaft 10 is integrally molded from, for example, a metal material and has a first section 11 and a second section 12 having different diameters arranged along the axial direction J. The axial direction J is, for example, parallel to the X-axis and perpendicular to the Y-axis and Z-axis. The first section 11 of the connecting shaft 10 has a circular outer and inner periphery, and the second section 12 of the connecting shaft 10 has a circular inner periphery. The outer diameter ΦC of the first section 11 is larger than the inner diameter ΦA of the second section 12 and gradually increases to a constant value along the direction away from the second section 12. The connecting shaft 10 further includes a housing space 13 that communicates between the front end 101 and the rear end 102 of the connecting shaft 10 along the axial direction J. The outer surface of the second section 12 of the connecting shaft 10 forms an elliptical cam having a major axis length a and a minor axis length b. In this embodiment, the motor 20 is, for example, an outer rotor / inner stator type and comprises a stator 21, a rotating member 22, and a central shaft 23. The stator 21 is fixed to the periphery of the central shaft 23. The central shaft 23 penetrates the stator 21 and is installed along the axial direction J. The rotating member 22 is, for example, a magnet, and is spatially corresponding to the stator 21 and is installed on the outer periphery of the stator 21. When the motor 20 is operated, the stator 21 drives the rotating member 22 to rotate around the central axis 23. In this embodiment, the inner surface of the first section 11 of the connecting shaft 10 is concentrically sleeved with respect to the rotating member 22 of the motor 20 along the radial direction, together forming the rotor of the motor 20, and the central axis 23 and the stator 21 are housed in the housing space 13.In this embodiment, the gearbox 30 is mounted concentrically on the connecting shaft 10 along the radial direction and connected to the motor 20 via the connecting shaft 10. The gearbox 30 includes a gearbox output shaft 31 connected to the outer surface of the second section 12 of the connecting shaft 10 via a first bearing 41. This allows the motor 20 and the gearbox 30 to be combined via the connecting shaft 10 to form an integrated drive unit. Compared to conventional motor gearbox devices arranged and connected along the axial direction, the integrated unit 1 of the present invention saves on the number of parts, simplifies the assembly structure of the motor 20 and the gearbox 30, achieves the objective of thinning, and maintains the characteristics of a high reduction ratio.

[0031] In this embodiment, the first section 11 and the second section 12 of the connecting shaft 10 are integrally formed and can be considered structurally as a single component of the integrated machine 1. However, since the connecting shaft 10 is connected between the motor 20 and the reduction gear 30, multiple transmission functions are integrated into a single component. In this embodiment, after the connecting shaft 10 is connected to the motor 20, it forms a motor output shaft that is connected to the rotating member 22 of the motor 20 via the inner surface of the first section 11 of the connecting shaft 10. When the stator 21 of the motor 20 rotates the rotating member 22, because the connecting shaft 10 is an integral single component, the connecting shaft 10 rotates in sync with the rotating member 22 of the motor 20 and can further transmit the kinetic energy generated by the motor 20 to the outside as a motor output shaft. For example, the reduction gear 30 is driven via the connecting shaft 10.

[0032] On the other hand, in this embodiment, after the connecting shaft 10 is connected to the reduction gear 30, it forms a reduction gear input shaft that is connected to the reduction gear output shaft 31 of the reduction gear 30 via the outer surface of the second section 12 of the connecting shaft 10 and the first bearing 41. When the momentum of the motor 20 is transmitted through the connecting shaft 10 and the connecting shaft 10 is rotationally driven, the connecting shaft 10 can function as a reduction gear input shaft. In cooperation with the internal gear assembly of the reduction gear 30, the momentum introduced into the reduction gear 30 by the connecting shaft 10 can be output via the reduction gear output shaft 31 after the rotational speed is adjusted by the reduction gear 30.

[0033] In this embodiment, in order to provide the function of a gearbox input shaft, the outer surface of the second section 12 of the connecting shaft 10 forms an elliptical cam having a major axis length a and a minor axis length b. The outer diameter ΦC of the first section 11 is greater than the major axis length a, and the minor axis length b is greater than the inner diameter ΦA of the second section 12, i.e., b > ΦA, thereby preventing the minor axis of the elliptical cam from contacting the inner diameter of the second section 12. Also, in this embodiment, the minor axis length b is not greater than the outer diameter ΦC of the first section 11, i.e., b ≤ ΦC. The outer diameter ΦC of the first section 11 corresponds to the required housing space 13 for the motor 20, and as the outer diameter ΦC of the first section 11 increases, the corresponding housing space 13 for housing the motor 20 of the connecting shaft 10 also increases.

[0034] In this embodiment, the gear meshing in the reduction gear 30 has a pitch circle diameter (PCD) ΦD related to the internal gear parameters of the reduction gear 30. Since the reduction gear 30 is mounted on the outer surface of the connecting shaft 10 and the motor 20 is located on the inner surface of the first section 11 of the connecting shaft 10, the pitch circle diameter (PCD) ΦD is not smaller than the outer diameter ΦC of the first section 11, i.e., ΦC ≤ ΦD.

[0035] Furthermore, in this embodiment, a design parameter X is defined for the pitch circle diameter (PCD) ΦD, based on the difference between the major axis length a and the minor axis length b, and the value of the design parameter X is equal to pitch circle diameter ΦD / (major axis length a - minor axis length b). Test results show that the motor 20 and gearbox 30 incorporated in the integrated machine 1 of the present invention can obtain a better reduction ratio when the design parameter X is in the range of 18 to 92. In other words, by mounting the connecting shaft 10 concentrically with the motor 20 and gearbox 30 along the radial direction, the integrated machine 1 of the present invention achieves a thinner profile, and further controls the range of the design parameter X to 18 ≤ X ≤ 92, thereby maintaining the characteristics of a high reduction ratio in the arrangement of the motor 20 and gearbox 30.

[0036] In this embodiment, the motor 20 is, for example, an outer rotor / inner stator type. The outer surface of the second section 12 of the connecting shaft 10 is connected to the reduction gear 30 via the first bearing 41, and correspondingly, the inner surface of the second section 12 of the connecting shaft 10 is concentrically fitted radially to the central shaft 23 of the motor 20 via the second bearing 42. In this embodiment, the reduction gear output shaft 31, the first bearing 41, the second section 12 of the connecting shaft 10, the second bearing 42, and the central shaft 23 of the motor 20 are arranged radially from outside to inside, and the reduction gear output shaft 31, the first bearing 41, the second section 12 of the connecting shaft 10, and the second bearing 42 are arranged facing each other to form a coaxial structure, which helps optimize space and shortens the axial length J to achieve a thinner design.

[0037] In this embodiment, the central shaft 23 of the motor 20 extends outward through the front end 101 of the connecting shaft 10, and the motor 20 includes a circuit board 24, which is fixed to the outer peripheral edge of the central shaft 23, housed in a housing space 13, and adjacent to the front end 101 of the connecting shaft 10. In this embodiment, the circuit board is connected to the outside via motor lead wires 25, which are connected to the outside through the hollow portion of the central shaft 23. In this embodiment, the motor 20 spatially corresponds to the front end of the connecting shaft 10 and further includes an encoder 26 for measuring information on the rotational speed and angle of the connecting shaft 10. The encoder 26 is fixed, for example, to an end cap 40 or to the front end 101 of the connecting shaft 10.

[0038] Furthermore, in this embodiment, the gearbox-motor integrated unit 1 further includes an end cap 40 adjacent to the front end 101 of the connecting shaft 10 and fixed to one end of the central shaft 23 of the motor 20. In this embodiment, the front end 101 of the connecting shaft 10 is connected to the end cap 40 via a third bearing 43. The third bearing 43 is, for example, a particular depth gauge bearing. In this embodiment, the gearbox 30 is connected to the end cap 40 via a fixed end 32. In this embodiment, the fixed end 32 of the gearbox, the first section 11 of the connecting shaft 10, the rotating member 22 of the motor 20, the stator 21, and the central shaft 23 are arranged radially from outside to inside, and the fixed end 32 of the gearbox, the first section 11 of the connecting shaft 10, the rotating member 22 of the motor 20, and the stator 21 are arranged facing each other to form a coaxial structure, which helps optimize space and shortens the axial length J to achieve a thinner design.

[0039] In this embodiment, the rotating member 22 is, for example, a magnet and is installed annularly on the inner surface of the first section 11. The present invention is not limited to a configuration in which the rotating member 22 is fixed to the inner surface of the first section 11. In one embodiment, the rotating member 22 is, for example, an annular magnet and is directly bonded to the inner surface of the first section 11. In one embodiment, the rotating member 22 comprises, for example, a plurality of magnets installed annularly at equal intervals. In other embodiments, the number, dimensions, type, and method of connection and fixing of the connecting shaft 10 to the inner surface of the first section 11 of the rotating member 22 can be adjusted according to the requirements of the actual application. The present invention is not limited thereto and is not repeated herein.

[0040] In this embodiment, the housing space 13 formed by the inner circumferential wall 103 of the connecting shaft 10 houses the stator 21, rotating member 22, central shaft 23, and circuit board 24 of the motor 20. In this embodiment, an oil reservoir 33 is formed between the reduction gear 30 and the outer circumferential wall 104 of the connecting shaft 10 (including the first section 11 and the second section 12), which can function, for example, as a lubrication oil passage for the reduction gear 30. Since the oil reservoir 33 is located outside the integrated connecting shaft 10 and belongs to a separate and independent area from the housing space 13 that houses the motor 20 inside the connecting shaft 10, the stator 21, rotating member 22, central shaft 23, and circuit board 24 of the motor 20 in the housing space 13 are not contaminated by the lubrication oil of the reduction gear 30. In other embodiments, the area of ​​the oil reservoir 33 and the method of isolation from the housing space 13 can be adjusted according to the requirements of the actual application. The present invention is not limited thereto and is not repeated herein.

[0041] Figure 5 is a cross-sectional view of a gearbox-motor integrated machine according to a second preferred embodiment of the present invention. In this embodiment, the gearbox-motor integrated machine 1a is similar to the gearbox-motor integrated machine 1 shown in Figures 1 to 4, and the same reference numerals represent the same components, structure and function, which are omitted from this description. In this embodiment, the gearbox-motor integrated machine 1a further comprises a ball spline 50 connected to the gearbox output shaft 31 of the gearbox 30a. The ball spline 50 comprises a spline nut 51, a spline shaft 52, and a plurality of balls 53, the spline shaft 52 passing through the central axis 23 of the motor 20 along the axial direction J and comprising a plurality of guide grooves 521 extending along the axial direction J. The plurality of guide grooves 521 are spatially corresponding to the plurality of balls 53 so as to partially accommodate the plurality of balls 53. Furthermore, the spline nut 51 is concentrically sleeved on the spline shaft 52 along the radial direction, fixed to the output end 31 of the reducer, and connected to the spline shaft 52 via a plurality of balls 53. The balls 53 are, for example, enclosed within the spline nut 51 as a transmission medium between the spline nut 51 and the spline shaft 52, and the present invention is not limited to the placement of the balls 53 between the spline nut 51 and the spline shaft 52. In this embodiment, the spline nut 51 is, for example, formed as a single component integral with the reducer output shaft 31. In other embodiments, the fixed connection between the spline nut 51 and the reducer output shaft 31 can be achieved by a locking component such as a screw. The present invention is not limited to this. Note that the connection between the reducer output shaft 31 and the spline nut 51 allows the reducer-motor integrated machine 1a to be directly connected to the ball spline 50 and rotate along the axial direction J, enabling the application of a high reduction ratio and obtaining higher transmission torque with better cost advantages.The spline shaft 52 of the ball spline 50 passes through the central shaft 23 of the motor 20, and the spline nut 51 is directly fixedly connected to or integrally formed with the output end 31 of the reducer, thereby simplifying and compacting the overall structure, achieving a high reduction ratio, and obtaining high transmission torque. Of course, the present invention is not limited thereto. In other embodiments, the reducer output shaft 31 of the reducer 30a may be connected to, for example, another spline or screw, and the ball spline 50 may be replaced with, for example, a rotary ball screw. Compared to conventional pulley-driven splines or screws, the integrated machine 1a of the present invention, by combining the ball spline 50 or screw, helps to achieve a high reduction ratio, maintain transmission rigidity, increase rotational torque, and effectively improve space volume utilization.

[0042] As described above, the present invention provides an integrated motor-reducer unit that improves upon the problem that conventional coaxial motor reducers have difficulty reducing overall volume and achieving a thin profile while maintaining high reduction ratio characteristics, by integrating the arrangement of the motor and reducer. The reducer and motor are combined by an integrated connecting shaft, which has a first section and a second section with different diameters arranged in the axial direction, forming different housing spaces. Furthermore, the outer rotor motor and the reducer are mounted concentrically along the radial direction to form parallel axes, and the connecting shaft is positioned radially midway between the outer rotor motor and the reducer input shaft, which helps optimize space. In addition, the integrally formed connecting shaft simultaneously provides functions equivalent to the output shaft of the outer rotor motor and the input shaft of the reducer, with the large-diameter first section constituting, for example, the output shaft of the outer rotor motor, and the small-diameter second section constituting, for example, the input shaft of the reducer, which helps simplify the connection between the output shaft of the outer rotor motor and the input shaft of the reducer. Two sets of bearings are mounted concentrically along the radial direction via the second section of the connecting shaft, which helps shorten the axial length and achieve a thin profile. Furthermore, the first section, which provides the function of the outer rotor motor output shaft, is perfectly circular, and the outer diameter of the first section can be designed according to the required housing space for the motor and the pitch circle diameter (PCD) of the gear meshing in the reducer. The second section, which provides the function of the reducer input shaft, is an elliptical cam, and under the condition that the minor axis length of the elliptical cam does not touch the inner diameter of the second section and does not exceed the outer diameter of the first section, the pitch circle diameter of the gear meshing in the reducer is given a design parameter within a specific range for the difference between the major axis length and the minor axis length of the elliptical cam. The motor and reducer combined by the integrated connecting shaft of the present invention maintain the characteristics of a high reduction ratio. Since independent spaces are provided inside and outside the integrated connecting shaft, the space between the outer circumferential wall of the connecting shaft and the reducer can be, for example, an oil reservoir, and the inside of the connecting shaft, as an independent region housing the motor and encoder, is not contaminated by the lubricating oil on the reducer side.On the other hand, the integrated gearbox-motor unit can be directly connected to a ball spline and rotate along the axial direction, enabling the application of high reduction ratios and achieving higher transmitted torque with better cost advantages. The spline shaft of the ball spline can pass through the central axis of the motor, and the spline nut is directly fixed to the output end of the gearbox to form an integrated structure. This simplifies and compacts the overall structure, improves the utilization of space volume, and achieves high reduction ratios, resulting in high transmitted torque.

[0043] Those skilled in the art may make various modifications to this invention, but will not deviate from the scope defined by the claims. [Explanation of Symbols]

[0044] 1, 1a: Machine with integrated gearbox and motor. 10:Connection shaft 101: Front end 102: Rear end 103:Inner wall 104:Outer wall 11: Section 1 12: Section 2 13: Containment Space 20: Motor 21: Status 22: Rotating member 23: Central axis 24: Circuit board 25: Motor lead wire 26: Encoder 30, 30a: Reducer 31: Reducer output shaft 32: Fixed end 33: Oil reservoir 40: End cap 41: First bearing 42: Second bearing 43: Third bearing 50: Ball spline 51: Spline nut 52: Spline shaft 521: Guide groove 53: Ball a: Major axis length b: Short axis length ΦA: Inner diameter of the second section ΦB: Inner diameter of the first section ΦC: Outer diameter of the first section ΦD, PCD: Pitch circle diameter J: Axial direction X, Y, Z: Axes

Claims

1. A gearbox-motor integrated machine comprising a connecting shaft, a motor, and a reduction gear, The connecting shaft comprises a first section, a second section, and a housing space, the first section and the second section are arranged axially, the housing space communicates between the front end and the rear end of the connecting shaft along the axial direction, the outer surface of the second section of the connecting shaft forms an elliptical cam, and the outer diameter of the first section is greater than the major axis length of the elliptical cam. The motor is housed within the housing space and connected to the inner surface of the first section, and the motor further comprises an encoder, a portion of which spatially corresponds to the front end of the connecting shaft and is fixed to the inner surface of the first section of the connecting shaft. The reduction gear is connected to the outer surface of the second section, The connecting shaft forms a reduction gear input shaft which is directly connected to the reduction gear output shaft of the reduction gear via the outer surface of the second section of the connecting shaft and the first bearing. A machine with an integrated gearbox and motor.

2. The motor comprises a stator, a rotating member spatially corresponding to the stator, and a central shaft that penetrates the stator and is installed along the axial direction. The gearbox-motor integrated machine according to claim 1, wherein the inner surface of the first section of the connecting shaft is concentrically fitted to the rotating member of the motor along the radial direction, together forming the rotor of the motor, and the central shaft and the stator are housed in the housing space.

3. The gearbox-motor integrated machine according to claim 2, further comprising an end cap adjacent to the front end of the connecting shaft and fixed to one end of the central shaft of the motor.

4. The fixed end of the reduction gear is connected to the end cap, the fixed end of the reduction gear, the first section of the connecting shaft, the rotating member of the motor, the stator, and the central shaft are arranged radially from the outside to the inside, and the fixed end of the reduction gear, the first section of the connecting shaft, the rotating member of the motor, and the stator are arranged facing each other, as described in claim 3.

5. The reducer / motor integrated machine according to claim 3, wherein the encoder is configured to measure information on the rotational speed and angle of the connecting shaft, and a part of the encoder is fixed to the end cap.

6. The front end of the connecting shaft is connected to the end cap via a third bearing, as described in claim 3, for the integrated gearbox and motor machine.

7. The gearbox-motor integrated machine according to claim 2, wherein the gearbox comprises a gearbox output shaft connected to the outer surface of the second section of the connecting shaft via the first bearing, and is concentrically mounted on the connecting shaft along the radial direction.

8. The gearbox-motor integrated machine according to claim 7, wherein the inner surface of the second section of the connecting shaft is fitted concentrically with the central axis of the motor along the radial direction via a second bearing.

9. The gearbox-motor integrated machine according to claim 8, wherein the gearbox output shaft, the first bearing, the second section of the connecting shaft, the second bearing, and the central shaft of the motor are arranged radially from the outside to the inside, and the gearbox output shaft, the first bearing, the second section of the connecting shaft, and the second bearing are arranged facing each other.

10. The gearbox-motor integrated machine according to claim 1, wherein the outer diameter of the first section gradually increases to a certain value along the direction away from the second section.

11. The gearbox-motor integrated machine according to claim 2, wherein the central shaft of the motor extends outward through the front end of the connecting shaft, the motor is fixed to the outer peripheral edge of the central shaft, is housed in the housing space, and includes a circuit board adjacent to the front end of the connecting shaft.

12. The gearbox-motor integrated machine according to claim 11, wherein the circuit board is connected to the outside via motor lead wires, and the motor lead wires are connected to the outside through the hollow portion of the central shaft.

13. The gearbox-motor integrated machine according to claim 1, wherein the elliptical cam has the long axis length and the short axis length, the short axis length being greater than the inner diameter of the second section and not greater than the outer diameter of the first section.

14. The gear meshing in the reduction gear has a pitch circle diameter that is not smaller than the outer diameter of the first section, as described in claim 13.

15. The gearbox-motor integrated machine according to claim 14, wherein the pitch circle diameter is 18 to 92 times the difference between the major axis length and the minor axis length.

16. The gearbox and motor integrated machine according to claim 1, wherein the first section and the second section of the connecting shaft are integrally formed.

17. The gearbox-motor integrated machine according to claim 1, wherein the connecting shaft forms a motor output shaft that is connected to the rotating member of the motor via the inner surface of the first section of the connecting shaft, and when the motor rotates, the gearbox is driven via the connecting shaft.

18. The reduction gear further comprises a ball spline connected to the output shaft of the reduction gear, The gearbox-motor integrated machine according to claim 1, wherein the ball spline comprises a spline nut, a spline shaft, and a plurality of balls, the spline shaft passing through the central axis of the motor along the axial direction, the spline nut being fitted concentrically to the spline shaft along the radial direction and fixed to the output end of the gearbox, and connected to the spline shaft via the plurality of balls.

19. The gearbox-motor integrated machine according to claim 1, wherein an oil reservoir is formed between the gearbox and the outer circumferential wall of the connecting shaft.

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