Actuator with two-stage planetary reducing mechanism and robot joint

Abstract

The utility model discloses an actuator with a two-stage planetary reducing mechanism and a robot joint. The actuator with the two-stage planetary reducing mechanism comprises a shell and a motor, the shell comprises a side wall, a top wall and a bottom wall, an inner gear ring is installed in the shell, and an installation space is defined by the inner edge face of the inner gear ring. A first sun gear, a first planet gear, a first planet carrier, a second sun gear, a second planet gear and a second planet carrier are arranged in the installation space, the first planet gear is connected to the first planet carrier in a pivoted mode and meshed between the inner gear ring and the first sun gear, and the second sun gear is synchronously connected with the first planet carrier. The second planet gear is pivoted on the second planet carrier and is meshed between the inner gear ring and the second sun gear; the lower end of the first sun gear is connected with the output end of the motor, and the upper end of the second planet carrier is pivoted to the top wall of the shell. According to the actuator, the space in the shell can be reasonably utilized, so that the interior of the actuator has a relatively compact structure, and particularly, the axial size of the actuator is greatly reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of robot driving, in particular to an actuator with a two-stage planetary reduction mechanism and a robot joint. Background Art

[0002] The actuator is an important component of the robot joint, which is used to provide power for the relative movement between the two moving parts of the robot joint and accurately control the movement angle of the two moving parts in the robot joint. The actuator usually includes a housing, a motor, and a reduction mechanism. The reduction mechanism usually adopts a planetary reduction mechanism. In order to increase the transmission ratio, a two-stage planetary reduction mechanism is usually set inside the actuator. The two-stage planetary reduction mechanism is arranged axially in the actuator, and is equipped with an inner ring gear, a sun gear, a planetary gear and a planetary carrier. This results in a large axial dimension of the actuator, and a large installation space needs to be reserved in the robot joint, resulting in an unreasonable spatial layout at the robot joint, and even affecting the overall layout of the robot. Utility Model Content

[0003] The utility model aims to solve at least one of the technical problems existing in the prior art. To this end, the purpose of the utility model is to provide an actuator and a robot joint with a two-stage planetary reduction mechanism to solve the problem in the prior art that the actuator has a large axial size and is difficult to reasonably arrange at the robot joint.

[0004] The purpose of the utility model is achieved by the following technical solutions:

[0005] An actuator with a two-stage planetary reduction mechanism comprises a housing and a motor;

[0006] The shell includes a side wall, a top wall located at the top of the side wall, and a bottom wall located at the bottom of the side wall. An inner gear ring fixedly matched with the shell is installed inside the shell, and the inner edge surface of the inner gear ring encloses an installation space;

[0007] A first sun gear, a first planet gear, a first planet carrier, a second sun gear, a second planet gear, and a second planet carrier are arranged in the installation space. The first planet gear is pivotally connected to the first planet carrier and meshed between the inner gear ring and the first sun gear. The second sun gear is synchronously connected to the first planet carrier. The second planet gear is pivotally connected to the second planet carrier and meshed between the inner gear ring and the second sun gear.

[0008] The lower end of the first sun gear protrudes from the bottom of the installation space to be connected to the output end of the motor, and the upper end of the second planet carrier protrudes from the top of the installation space and is pivotally connected to the top wall of the housing through a first bearing;

[0009] The lower surface of the top wall is provided with an upwardly concave annular groove, the outer peripheral edge of the annular groove is provided with a locking groove recessed toward the radially outer side of the actuator, the top surface of the inner gear ring is provided with an annular convex rib protruding upward and embedded in the annular groove, the outer edge surface of the annular convex rib is provided with a locking block clamped in the locking groove, and the top wall is provided with a locking bolt, which passes downward through the top wall and is screwed into a threaded hole provided on the top surface of the locking block, and the top wall is pressed downward by the nut of the locking bolt to fix the top wall and the inner gear ring.

[0010] According to the actuator with a two-stage planetary reduction mechanism in the embodiment of the utility model, the first sun gear, the first planetary gear, the first planet carrier, the second sun gear, the second planetary gear, the second planet carrier and the inner ring gear form a two-stage planetary reduction mechanism inside the outer shell. The two-stage planetary reduction mechanism shares the inner ring gear, and the two-stage planetary reduction mechanism is basically accommodated in the installation space surrounded by the inner ring gear. The space inside the outer shell can be reasonably utilized, so that the interior of the actuator has a more compact structure, especially greatly reducing the axial size of the actuator, so that the actuator can be reasonably arranged in the robot joint.

[0011] The annular convex rib cooperates with the annular groove, and the positioning block cooperates with the positioning groove, so as to position the inner gear ring and the top wall in the radial and circumferential directions of the actuator. When the axial dimension of the actuator is greatly reduced, the installation accuracy of the inner gear ring and the top wall is still improved. After positioning, the top wall and the inner gear ring are fixed with locking bolts, which simplifies the assembly process of the inner gear ring and the outer shell.

[0012] In a preferred embodiment, the top wall is fixedly connected to the side wall in a detachable manner, and a mounting surface is provided on the top wall, which extends along the axial direction of the actuator and is opposite to the outer peripheral wall of the second planet carrier, and the inner ring of the first bearing is tightly matched with the outer peripheral wall of the second planet carrier, and the outer ring of the first bearing is tightly matched with the mounting surface. A first bearing is provided between the top wall and the second planet carrier, and the first bearing provides radial support to the second planet carrier, which is the output end flange of the actuator, so that the output end of the actuator can rotate smoothly, thereby improving the accuracy of the actuator.

[0013] In a preferred embodiment, the first planetary frame includes a first upper frame, a first lower frame detachably fixed to the first upper frame, and two first planetary wheels are arranged between the first upper frame and the first lower frame; the second planetary frame includes a second upper frame, a second lower frame detachably fixed to the second upper frame, and three second planetary wheels are arranged between the second upper frame and the second lower frame. The first planetary frame and the second planetary frame are arranged as a split structure, which can facilitate the installation of the first planetary wheel and the second planetary wheel. In addition, two first planetary wheels are installed on the first planetary frame, and three planetary wheels are installed on the second planetary frame, which ensures the transmission efficiency and meets the radial stress requirements while reducing the dead weight of the entire actuator.

[0014] In a preferred embodiment, a mounting hole is provided in the middle of the first lower bracket, and a second bearing is provided between the first sun gear and the inner wall of the mounting hole to pivotally connect the first sun gear and the first lower bracket; a mounting groove is provided on the second upper bracket, which is recessed upward from its lower surface, and the top of the axle of the second sun gear is embedded in the mounting groove, and a third bearing is provided between the second sun gear and the inner wall of the mounting groove to pivotally connect the second sun gear and the second upper bracket. The second bearing provides radial support to the first sun gear so that the first sun gear can rotate stably, and the third bearing provides radial support to the second sun gear so that the second sun gear can rotate stably, thereby improving the accuracy of the actuator; in addition, the mounting groove is provided to avoid the second sun gear, and the mounting hole is provided to avoid the first sun gear, which is conducive to further reducing the axial size of the actuator.

[0015] In a preferred embodiment, an accommodation space is formed between the outer edge surface of the inner gear ring and the inner edge surface of the side wall, and the motor is placed in the accommodation space. The motor includes a stator located at the periphery of the inner gear ring and fixed to the inner gear ring, and a rotor located between the stator and the side wall. The rotor is synchronously connected to the first sun gear through a connecting bracket located between the bottom wall and the stator. The motor is arranged around the periphery of the inner gear ring so that the motor and the inner gear ring overlap in the axial direction of the actuator, further reducing the axial size of the actuator, and using the inner gear ring as a component for fixing the stator so that the stator of the motor is fixedly matched with the housing, making the overall structure of the actuator more compact and facilitating the assembly of the motor into the actuator.

[0016] In a preferred embodiment, the top of the outer edge of the inner gear ring is provided with an upper limit rib protruding toward the radial outside of the actuator, and a limit ring is fixed to the bottom of the inner gear ring in a detachable manner, and a lower limit rib is provided on the limit ring. The upper limit rib and the lower limit rib are respectively pressed on the top and bottom surfaces of the stator to limit the freedom of the stator to move relative to the inner gear ring in the axial direction of the actuator. During assembly, the stator is sleeved from bottom to top on the periphery of the inner gear ring so that the upper limit rib abuts against the top surface of the stator, and then the limit ring is connected to the bottom of the inner gear ring with bolts, and the bolts are fully tightened so that the lower limit rib fully presses the bottom surface of the stator, which facilitates the assembly of the stator and the inner gear ring, can effectively prevent the stator from moving in the axial direction of the actuator, and enable the motor to work more stably.

[0017] In a preferred embodiment, the connecting bracket is provided with an inner supporting rib extending downward, the bottom wall is provided with an outer supporting rib extending upward and located outside the inner supporting rib, and a fourth bearing is provided between the inner supporting rib and the outer supporting rib to enable the connecting bracket to be pivotally connected with the bottom wall. The fourth bearing provides radial support for the connecting bracket, so that the connecting bracket can rotate stably, and then the rotor can rotate smoothly, so as to improve the working stability of the motor.

[0018] In a preferred embodiment, a downwardly recessed receiving groove is provided in the middle of the connecting bracket, a connecting seat fixedly matched with the connecting bracket is embedded in the receiving groove, a plug-in groove recessed downward from its top surface is provided on the connecting seat, the axle of the first sun gear is plugged into the plug-in groove from top to bottom, and abutment planes are respectively provided on the inner wall of the plug-in groove and the outer edge surface of the axle of the first sun gear, and the two abutment planes cooperate to prevent the axle of the first sun gear from rotating relative to the connecting seat. The first sun gear is synchronously connected to the connecting bracket through the connecting seat, and during assembly, the first sun gear can be loaded into the plug-in groove from top to bottom, thereby facilitating the assembly of the first sun gear and the connecting bracket, and then facilitating the overall assembly of the actuator.

[0019] A robot joint comprises the above-mentioned actuator with a two-stage planetary reduction mechanism.

[0020] The drawings in the specification, which constitute a part of the present application, are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation on the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the cutaway structure of the utility model;

[0022] Figure 2 for Figure 1 Schematic diagram of the structure of the inner gear ring;

[0023] Figure 3 for Figure 1 Schematic diagram of the structure of the middle top wall;

[0024] Figure 4 for Figure 1 The enlarged schematic diagram of point A in the middle;

[0025] Figure 5 for Figure 1 The enlarged schematic diagram of point B in the middle;

[0026] Figure 6 for Figure 1 Schematic diagram of the assembly of the middle bottom wall and the first sun gear;

[0027] Figure 7 It is a schematic diagram of the exploded structure of the two-stage planetary reduction mechanism of the utility model.

[0028] In the figure: 10, housing; 11, side wall; 12, top wall; 121, annular groove; 122, positioning groove; 123, mounting surface; 13, bottom wall; 131, outer support rib; 14, fourth bearing; 15, first bearing; 20, motor; 21, stator; 22, rotor; 23, connecting bracket; 231, inner support rib; 232, receiving groove; 30, inner gear ring; 301, upper limit rib; 31, annular convex rib; 32, positioning block; 33, threaded hole; 34 , limiting ring; 341, lower limiting rib; 41, first sun gear; 411, first abutment plane; 42, first planetary gear; 431, first upper bracket; 432, first lower bracket; 4321, mounting hole; 44, connecting seat; 441, plug-in slot; 442, second abutment plane; 45, second bearing; 51, second sun gear; 52, second planetary gear; 531, second upper bracket; 5311, mounting slot; 532, second lower bracket; 54, third bearing. DETAILED DESCRIPTION

[0029] Below, in conjunction with the accompanying drawings and specific implementation methods, the utility model is further described. It should be noted that, under the premise of no conflict, the various embodiments described below or the various technical features can be arbitrarily combined to form a new embodiment. Except for special instructions, the materials and equipment used in this embodiment can be purchased from the market. Examples of the embodiments are shown in the accompanying drawings, in which the same or similar numbers throughout represent the same or similar elements or elements with the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and cannot be understood as limiting the present application.

[0030] In the description of the present application, it should be understood that the terms "upper", "lower", "front", "back", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as a limitation on the present application. In the description of the present application, "plurality" means two or more, unless otherwise precisely and specifically specified.

[0031] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "connected", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, or it can be connected through an intermediary medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0032] The terms "first", "second", etc. in the specification and claims of this application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0033] Please refer to Figure 1-7 As shown, an actuator with a two-stage planetary reduction mechanism of the utility model includes a housing 10 and a motor 20; the housing 10 includes a side wall 11, a top wall 12, and a bottom wall 13, the top wall 12 is located at the top of the side wall 11, and the bottom wall 13 is located at the bottom of the side wall 11, and an inner gear ring 30 fixedly matched with the housing 10 is installed inside the housing 10, and the inner edge surface of the inner gear ring 30 forms an installation space, and a first sun gear 41, a first planetary gear 42, a first planet carrier, a second sun gear 51, a second planetary gear 52, and a second planet carrier are arranged in the installation space. The first sun gear 41, the first planetary gear 42, the first planet carrier, the second sun gear 51, the second planetary gear 52, and the second planet carrier are arranged. 1. The second planetary gear 52, the second planetary carrier and the inner gear ring 30 form a two-stage planetary reduction mechanism inside the housing 10. Specifically, the lower end of the axle of the first sun gear 41 protrudes from the bottom of the installation space and is connected to the output end of the motor 20. The first planetary gear 42 is pivoted to the first planetary carrier and meshes between the inner gear ring 30 and the first sun gear 41. The second sun gear 51 is synchronously connected to the first planetary carrier. The second planetary gear 52 is pivoted to the second planetary carrier and meshes between the inner gear ring 30 and the second sun gear 51. The upper end of the second planetary carrier protrudes from the top of the installation space and is pivoted to the top wall 12 of the housing 10 through the first bearing 15.

[0034] In the utility model, the first sun gear 41, the first planetary gear 42, the first planetary carrier, the second sun gear 51, the second planetary gear 52, the second planetary carrier and the inner ring gear 30 form a two-stage planetary reduction mechanism inside the outer shell 10. The two-stage planetary reduction mechanism shares the inner ring gear 30, and the two-stage planetary reduction mechanism is basically accommodated in the installation space surrounded by the inner ring gear 30. The space inside the outer shell 10 can be reasonably utilized, so that the interior of the actuator has a more compact structure, especially greatly reducing the axial size of the actuator, so that the actuator can be reasonably arranged in the robot joint.

[0035] In a preferred embodiment, an upwardly recessed annular groove 121 is provided on the lower surface of the top wall 12, and a retaining groove 122 recessed toward the radially outer side of the actuator is provided on the outer peripheral edge of the annular groove 121, and an upwardly protruding annular rib 31 is provided on the top surface of the inner gear ring 30, and the annular rib 31 is upwardly snapped into the annular groove 121, and a retaining block 32 is provided on the outer edge surface of the annular rib 31, and the retaining block 32 is correspondingly snapped into the retaining groove 122, and the annular rib 31 cooperates with the annular groove 121 to limit the freedom of movement of the inner gear ring 30 relative to the top wall 12 in the radial direction of the actuator, that is, the inner gear ring 30 is positioned in the radial direction of the actuator, and the retaining block 32 cooperates with the retaining groove 122 to limit the freedom of movement of the inner gear ring 30 relative to the top wall 12 in the circumferential direction of the actuator, that is, the inner gear ring 30 is positioned in the circumferential direction of the actuator. A locking bolt is provided on the top wall 12. The locking bolt passes through the top wall 12 downward and is screwed into the threaded hole 33 provided on the top surface of the positioning block 32. The nut of the locking bolt presses the top wall 12 downward. After tightening the locking bolt, the inner gear ring 30 is fixed to the bottom of the top wall 12, and then the inner gear ring 30 is fixed to the top wall 12 in the axial direction of the actuator. The annular rib 31 cooperates with the annular groove 121, and the positioning block 32 cooperates with the positioning groove 122, so as to position the inner gear ring 30 and the top wall 12 in the radial and circumferential directions of the actuator, thereby improving the installation accuracy of the inner gear ring 30 and the top wall 12. After positioning, the top wall 12 is fixed to the inner gear ring 30 by using the locking bolt, thereby simplifying the assembly process of the inner gear ring 30 and the housing 10.

[0036] The top wall 12 is fixedly connected to the side wall 11 in a detachable manner. For example, the top wall 12 can be fixed to the side wall 11 by bolts extending along the axial direction of the actuator. A mounting surface 123 extending along the circumferential direction of the actuator is provided on the top wall 12. The mounting surface 123 is located outside the outer peripheral wall of the second planetary frame to be arranged opposite to the outer peripheral wall of the second planetary frame. The inner ring of the first bearing 15 is tightly matched with the outer peripheral wall of the second planetary frame, and the outer ring of the first bearing 15 is tightly matched with the mounting surface 123. Thus, the second planetary frame is pivotally connected to the top wall 12, and the second planetary frame can be used as the output end flange of the actuator. The first bearing 15 is provided between the top wall 12 and the second planetary frame. The first bearing 15 provides radial support to the second planetary frame as the output end flange of the actuator, so that the output end of the actuator can rotate smoothly, thereby improving the accuracy of the actuator. The first planetary frame includes a first upper bracket 431 and a first lower bracket 432, which are fixed together by bolt connection or other detachable connection methods, and two first planetary gears 42 are arranged between the first upper bracket 431 and the first lower bracket 432; the second planetary frame includes a second upper bracket 531 and a second lower bracket 532, which are fixed together by bolt connection or other detachable connection methods. The first planetary frame and the second planetary frame are arranged as a split structure, which can facilitate the installation of the first planetary gear 42 and the second planetary gear 52. In addition, two first planetary gears 42 are installed on the first planetary frame, and three second planetary gears 52 are installed on the second planetary frame, which ensures the transmission efficiency and meets the radial stress requirements while reducing the dead weight of the entire actuator. A mounting hole 4321 is provided in the middle of the first lower bracket 432, and a second bearing 45 is provided between the first sun gear 41 and the inner wall of the mounting hole 4321, and the second bearing 45 pivots the first sun gear 41 and the first lower bracket 432 together; a mounting groove 5311 which is recessed upward from its lower surface is provided on the second upper bracket 531, and the top of the axle of the second sun gear 51 is embedded in the mounting groove 5311, and a third bearing 54 is provided between the axle of the second sun gear 51 and the mounting groove 5311, and the third bearing 54 pivots the second sun gear 51 and the second upper bracket 531 together. The second bearing 45 provides radial support to the first sun gear 41 so that the first sun gear 41 can rotate stably, and the third bearing 54 provides radial support to the second sun gear 51 so that the second sun gear 51 can rotate stably, thereby improving the accuracy of the actuator; in addition, a mounting groove 5311 is provided to avoid the second sun gear 51, and a mounting hole 4321 is provided to avoid the first sun gear 41, which is beneficial to further reduce the axial size of the actuator.

[0037] In another preferred embodiment, an accommodation space is formed between the outer edge surface of the inner gear ring 30 and the inner edge surface of the side wall 11 of the housing 10, and the accommodation space is annular. The motor 20 is a frameless torque motor, which is arranged in the annular accommodation space. The motor 20 includes a stator 21 and a rotor 22. The stator 21 is located at the periphery of the inner gear ring 30 and fixedly matched with the inner gear ring 30. The rotor 22 surrounds the periphery of the stator 21, so that the rotor 22 is placed between the stator 21 and the side wall 11. The rotor 22 is synchronously connected with the first sun gear 41 through a connecting bracket 23 located between the bottom wall 13 and the stator 21. The motor 20 is arranged around the periphery of the inner gear ring 30, so that the motor 20 and the inner gear ring 30 overlap in the axial direction of the actuator, further reducing the axial size of the actuator, and using the inner gear ring 30 as a component for fixing the stator 21, so that the stator 21 of the motor 20 is fixedly matched with the housing 10, so that the overall structure of the actuator is more compact, and it is convenient to assemble the motor 20 into the actuator.

[0038] In order to accurately position the motor 20 and facilitate the installation and fixation of the stator 21 and the inner gear ring 30, an upper limit rib 301 protruding toward the radial outside of the actuator is provided at the top of the outer edge surface of the inner gear ring 30, and a limit ring 34 is fixed to the bottom of the inner gear ring 30 by bolt connection or other detachable connection methods. A lower limit rib 341 is provided on the limit ring 34. The upper limit rib 301 is pressed on the top surface of the stator 21, and the lower limit rib 341 is pressed on the bottom surface of the stator 21. Therefore, the upper limit rib 301 and the lower limit rib 341 are used to limit the freedom of movement of the stator 21 relative to the inner gear ring 30 in the axial direction of the actuator. During assembly, the stator 21 is mounted on the outer periphery of the inner gear ring 30 from bottom to top, so that the upper limit rib 301 presses against the top surface of the stator 21, and then the limit ring 34 is connected to the bottom of the inner gear ring 30 with bolts, and the bolts are fully tightened so that the lower limit rib 341 fully presses the bottom surface of the stator 21. This facilitates the assembly of the stator 21 and the inner gear ring 30, and can effectively prevent the stator 21 from moving in the axial direction of the actuator, so that the motor 20 can work more stably.

[0039] The connecting bracket 23 is provided with an inner supporting rib 231 extending downward, and the bottom wall 13 is provided with an outer supporting rib 131 extending upward, the outer supporting rib 131 surrounds the periphery of the inner supporting rib 231, and a fourth bearing 14 is provided between the inner supporting rib 231 and the outer supporting rib 131, the inner ring of the fourth bearing 14 is tightly matched with the inner supporting rib 231, and the outer ring of the fourth bearing 14 is tightly matched with the outer supporting rib 131, and the connecting bracket 23 is pivotally connected to the bottom wall 13 by the fourth bearing 14. The fourth bearing 14 provides radial support for the connecting bracket 23, so that the connecting bracket 23 can rotate stably, and then the rotor 22 can rotate smoothly, so as to improve the working stability of the motor 20.

[0040] A downwardly recessed receiving groove 232 is provided in the middle of the connecting bracket 23, and a connecting seat 44 is embedded in the receiving groove 232. The connecting seat 44 is fixed to the connecting bracket 23 by bolts, and a plug-in groove 441 is provided on the connecting seat 44, which is recessed downward from its top surface. The axle of the first sun gear 41 is plugged into the plug-in groove 441 from top to bottom, and a second abutment plane 442 is provided on the inner wall of the plug-in groove 441. A first abutment plane 411 is provided on the axle of the first sun gear 41, and the first abutment plane 411 and the second abutment plane 442 are tightly matched with each other to prevent the axle of the first sun gear 41 from rotating relative to the connecting seat 44; the first sun gear 41 and the connecting bracket 23 are synchronously connected together through the connecting seat 44. During assembly, the first sun gear 41 can be loaded into the plug-in groove 441 from top to bottom, thereby facilitating the assembly of the first sun gear 41 and the connecting bracket 23, and then facilitating the overall assembly of the actuator. It should be noted that the second bearing 45 may be disposed between the connecting seat 44 and the first lower bracket 432 to provide radial support for the first sun gear 41 and improve the compactness of the internal structure of the actuator.

[0041] The robot joint of the utility model includes the above-mentioned actuator with a two-stage planetary reduction mechanism. Other structures of the robot joint are the same as those in the prior art and will not be described in detail here.

[0042] Although only certain components and embodiments of the present application have been illustrated and described, many modifications and changes may be conceived by those skilled in the art without actually departing from the scope and spirit of the claims, such as changes in the size, dimensions, structure, shape and proportion of the various elements, mounting arrangements, material usage, color, orientation, etc.

[0043] The above-mentioned implementation mode is only a preferred implementation mode of the embodiment of the utility model, and cannot be used to limit the scope of protection of the embodiment of the utility model. Any non-substantial changes and replacements made by technical personnel in this field on the basis of the embodiment of the utility model shall fall within the scope of protection required by the embodiment of the utility model.

Claims

1. An actuator with a two-stage planetary reduction mechanism, characterized in that: Including housing and motor; The shell includes a side wall, a top wall located at the top of the side wall, and a bottom wall located at the bottom of the side wall. An inner gear ring fixedly matched with the shell is installed inside the shell, and the inner edge surface of the inner gear ring encloses an installation space; A first sun gear, a first planet gear, a first planet carrier, a second sun gear, a second planet gear, and a second planet carrier are arranged in the installation space. The first planet gear is pivotally connected to the first planet carrier and meshed between the inner gear ring and the first sun gear. The second sun gear is synchronously connected to the first planet carrier. The second planet gear is pivotally connected to the second planet carrier and meshed between the inner gear ring and the second sun gear. The lower end of the first sun gear protrudes from the bottom of the installation space to be connected to the output end of the motor, and the upper end of the second planet carrier protrudes from the top of the installation space and is pivotally connected to the top wall of the housing through a first bearing; The lower surface of the top wall is provided with an upwardly concave annular groove, the outer peripheral edge of the annular groove is provided with a locking groove recessed toward the radially outer side of the actuator, the top surface of the inner gear ring is provided with an annular convex rib protruding upward and embedded in the annular groove, the outer edge surface of the annular convex rib is provided with a locking block clamped in the locking groove, and the top wall is provided with a locking bolt, which passes downward through the top wall and is screwed into a threaded hole provided on the top surface of the locking block, and the top wall is pressed downward by the nut of the locking bolt to fix the top wall and the inner gear ring.

2. The actuator with a two-stage planetary reduction mechanism according to claim 1, characterized in that: The top wall is fixedly connected to the side wall in a detachable manner, and a mounting surface is provided on the top wall, which extends along the axial direction of the actuator and is opposite to the outer peripheral wall of the second planetary carrier. The inner ring of the first bearing is tightly fitted with the outer peripheral wall of the second planetary carrier, and the outer ring of the first bearing is tightly fitted with the mounting surface.

3. The actuator with a two-stage planetary reduction mechanism according to claim 2, characterized in that: The first planetary carrier includes a first upper bracket and a first lower bracket detachably fixed to the first upper bracket, and two first planetary gears are arranged between the first upper bracket and the first lower bracket; the second planetary carrier includes a second upper bracket and a second lower bracket detachably fixed to the second upper bracket, and three second planetary gears are arranged between the second upper bracket and the second lower bracket.

4. The actuator with a two-stage planetary reduction mechanism according to claim 3, characterized in that: A mounting hole is provided in the middle of the first lower bracket, and a second bearing is provided between the first sun gear and the inner wall of the mounting hole to pivotally connect the first sun gear and the first lower bracket; a mounting groove is provided on the second upper bracket, which is recessed upward from its lower surface, and the top of the axle of the second sun gear is embedded in the mounting groove, and a third bearing is provided between the second sun gear and the inner wall of the mounting groove to pivotally connect the second sun gear and the second upper bracket.

5. The actuator with a two-stage planetary reduction mechanism according to claim 1, characterized in that: An accommodating space is formed between the outer edge surface of the inner gear ring and the inner edge surface of the side wall, and the motor is placed in the accommodating space. The motor includes a stator located at the periphery of the inner gear ring and fixed to the inner gear ring, and a rotor located between the stator and the side wall. The rotor is synchronously connected to the first sun gear through a connecting bracket located between the bottom wall and the stator.

6. The actuator with a two-stage planetary reduction mechanism according to claim 5, characterized in that: An upper limit rib protruding radially outward from the actuator is provided at the top of the outer edge of the inner gear ring, and a limit ring is detachably fixed to the bottom of the inner gear ring, on which a lower limit rib is provided. The upper limit rib and the lower limit rib are respectively pressed onto the top and bottom surfaces of the stator to limit the freedom of the stator to move axially relative to the inner gear ring of the actuator.

7. The actuator with a two-stage planetary reduction mechanism according to claim 6, characterized in that: The connecting bracket is provided with an inner supporting rib extending downward, the bottom wall is provided with an outer supporting rib extending upward and located outside the inner supporting rib, and a fourth bearing is provided between the inner supporting rib and the outer supporting rib to enable the connecting bracket to pivotally cooperate with the bottom wall.

8. The actuator with a two-stage planetary reduction mechanism according to claim 5, characterized in that: A downwardly recessed receiving groove is provided in the middle of the connecting bracket, and a connecting seat fixedly matched with the connecting bracket is embedded in the receiving groove. The connecting seat is provided with a plug-in groove recessed downward from its top surface, and the axle of the first sun gear is plugged into the plug-in groove from top to bottom. Abutment planes are respectively provided on the inner wall of the plug-in groove and the outer edge surface of the axle of the first sun gear, and the two abutment planes cooperate to prevent the axle of the first sun gear from rotating relative to the connecting seat.

9. A robot joint comprising the actuator with a two-stage planetary reduction mechanism according to any one of claims 1 to 8.

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