Speed reducer assembly

Abstract

The invention relates to the technical field of mechanical transmission, in particular to a speed reducer assembly which comprises a fixed flange plate, an output shaft, a plurality of first planet carriers, a plurality of first-stage planet gears, a power conversion gear ring, a plurality of second-stage planet gears, a second planet carrier, a fixed gear ring and an output flange plate. The first-stage planet gear drives a rotatable power conversion gear ring to finish first-stage speed reduction; the power conversion gear ring serves as a second-stage sun gear at the same time, a second outer gear of the power conversion gear ring drives a second-stage planet gear, and under the constraint of the fixed gear ring, the rotating second-stage planet gear is forced to revolve around the center line of the input shaft, so that a second planet carrier and an output flange plate fixed to the second planet carrier are driven to rotate together, and second-stage speed reduction is achieved. According to the structure, two stages of speed reduction share the same axial space, the power conversion gear ring serves as a core transmission part to be connected with the two stages in series, and the whole structure is ultrathin and compact.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of mechanical transmission, in particular to a speed reducer assembly. BACKGROUND

[0002] Planetary reducer is widely used in industrial robots, precision equipment and other fields due to its compact structure, large transmission ratio and strong carrying capacity. With the development of humanoid robots, collaborative robots and other technologies, high requirements are put forward for the compactness of joint modules, especially the axial size (thickness) needs to be as thin as possible to increase the flexibility and movement range of the robot.

[0003] The existing conventional planetary reducer (such as shown in Figure 1 ), usually realizes large reduction ratio by multi-stage series connection, but its overall axial size is still large, which is difficult to meet the design requirements of ultra-thin joints.

[0004] Other reducers, such as the patent document with authorization announcement number CN209130124U, although adopt split type planet carrier and thin type bearing to reduce the axial thickness, but its structure is still relatively complex, and when bearing large axial force, the internal gear assembly may have axial movement risk, affecting the transmission accuracy and stability.

[0005] Therefore, there is an urgent need for a speed reducer assembly that can realize axial ultra-thin design while ensuring large reduction ratio and carrying capacity. SUMMARY

[0006] The purpose of the present application is to provide a speed reducer assembly to solve the problems of thick axial size and complex multi-stage transmission structure of the existing technology.

[0007] To achieve the above purpose, the present application provides a speed reducer assembly, which comprises a fixed flange plate, an output shaft, a plurality of first planet carriers, a plurality of primary planetary gears, a power conversion ring gear, a plurality of secondary planetary gears, a second planet carrier, a fixed ring gear and an output flange plate. The output shaft is rotatably arranged at the center of the fixed flange plate, and the end of the output shaft extending into the interior of the fixed flange plate is provided with an input sun gear. A plurality of first planet carriers are fixedly arranged on the fixed flange plate and uniformly distributed around the input sun gear. One primary planetary gear is rotatably mounted on each first planet carrier, and a plurality of primary planetary gears are engaged with the input sun gear. The power conversion ring gear is rotatably arranged in the interior of the fixed flange plate, the inner ring of the power conversion ring gear is provided with a first inner tooth, the first inner tooth is engaged with a plurality of primary planetary gears, and the outer ring of the power conversion ring gear is provided with a second outer tooth. The inner side wall of the fixed flange plate is provided with the fixed gear ring, the inner side wall of the fixed gear ring is provided with a third inner gear, the second planet carrier is rotatably arranged in the interior of the fixed flange plate, a plurality of the second-level planet wheels are rotatably mounted on the second planet carrier, each of the second-level planet wheels is simultaneously meshed with the second outer gear and the third inner gear, and the output flange plate is fixedly arranged on the end face of the second planet carrier.

[0008] The inner wall of each of the first-level planet wheels is provided with a first needle roller between the outer wall of the mounting shaft of the corresponding first planet carrier.

[0009] The second planet carrier comprises a rotating disc and a plurality of connecting shafts, the rotating disc is rotatably arranged on the fixed flange plate and located on the side of the fixed gear ring away from the output flange plate, a plurality of mounting protrusions are fixedly arranged on the side of the output flange plate facing the rotating disc, a plurality of fixing pins are uniformly arranged on the rotating disc, each of the fixing pins is connected with one of the mounting protrusions, and the connecting shaft is arranged between each of two adjacent fixing pins.

[0010] The inner wall of each of the second-level planet wheels is provided with a second needle roller between the outer wall of the corresponding connecting shaft.

[0011] The side of the power conversion gear ring contacting the fixed flange plate and the side of the power conversion gear ring contacting the output flange plate are both provided with a plane needle roller bearing.

[0012] The side of the fixed gear ring contacting the rotating disc and the side of the fixed gear ring contacting the output flange plate are both provided with an annular groove, and a plurality of rolling balls are arranged in the interior of each of the annular grooves.

[0013] The speed reducer assembly comprises a fixed flange plate, an output shaft, a plurality of first planet carriers, a plurality of first-level planet wheels, a power conversion gear ring, a plurality of second-level planet wheels, a second planet carrier, a fixed gear ring and an output flange plate. The input sun gear drives the first-level planet wheels, and the first-level planet wheels drive the rotatable power conversion gear ring to complete the first-stage speed reduction. The power conversion gear ring simultaneously serves as a second-level sun gear, the second outer gear of the power conversion gear ring drives the second-level planet wheels, and the second-level planet wheels are forced to revolve around the center line of the input shaft under the constraint of the fixed gear ring, so as to drive the second planet carrier and the output flange plate fixedly arranged on the second planet carrier to rotate together, thereby realizing the second-stage speed reduction. The above structure shares the same axial space for two-stage speed reduction, and the power conversion gear ring is used as a core transmission part to connect the two stages, thereby significantly reducing the axial stacking thickness caused by the traditional series connection structure, and realizing the ultrathin and compact structure of the overall structure. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1 This is a cross-sectional structural diagram of a conventional planetary reducer as presented in the background section of this invention.

[0016] Figure 2 This is a cross-sectional structural schematic diagram of the speed reducer assembly provided by the present invention.

[0017] Figure 3 This is a schematic diagram of the transmission structure of the speed reducer assembly provided by the present invention.

[0018] Figure 4 This is a partial disassembled structural diagram of the speed reducer assembly provided by the present invention.

[0019] Figure 5 This invention provides Figure 4 A structural diagram from another perspective.

[0020] 101-Fixed flange, 102-Output shaft, 103-First planetary carrier, 104-First-stage planetary gear, 105-Power conversion gear ring, 106-Second-stage planetary gear, 107-Fixed gear ring, 108-Output flange, 109-Input sun gear, 110-First internal gear, 111-Second external gear, 112-Third internal gear, 113-First needle roller, 114-Rotating disc, 115-Connecting shaft, 116-Mounting protrusion, 117-Fixed pin, 118-Second needle roller, 119-Flat needle roller bearing, 120-Annular groove, 121-Ball bearing. Detailed Implementation

[0021] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0022] Please see Figures 1 to 5The application provides a speed reducer assembly, which comprises a fixed flange plate 101, an output shaft 102, a plurality of first planet carriers 103, a plurality of primary planet gears 104, a power conversion gear ring 105, a plurality of secondary planet gears 106, a second planet carrier, a fixed gear ring 107 and an output flange plate 108, the output shaft 102 is rotatably arranged at the center of the fixed flange plate 101, an input sun gear 109 is arranged at the end of the output shaft 102 extending into the interior of the fixed flange plate 101, a plurality of the first planet carriers 103 are fixedly arranged on the fixed flange plate 101 and uniformly distributed around the input sun gear 109, one primary planet gear 104 is rotatably arranged on each first planet carrier 103, and a plurality of the primary planet gears 104 are engaged with the input sun gear 109; The power conversion gear ring 105 is rotatably arranged in the interior of the fixed flange plate 101, the inner ring of the power conversion gear ring 105 is provided with a first inner tooth 110, the first inner tooth 110 is engaged with a plurality of the primary planet gears 104, and the outer ring of the power conversion gear ring 105 is provided with a second outer tooth 111. The fixed gear ring 107 is arranged on the inner side wall of the fixed flange plate 101, the inner side wall of the fixed gear ring 107 is provided with a third inner tooth 112, the second planet carrier is rotatably arranged in the interior of the fixed flange plate 101, a plurality of the secondary planet gears 106 are rotatably arranged on the second planet carrier, each secondary planet gear 106 is simultaneously engaged with the second outer tooth 111 and the third inner tooth 112, and the output flange plate 108 is fixedly arranged on the end face of the second planet carrier.

[0023] In the embodiment, the operation principle of the speed reducer assembly is that the input shaft drives the input sun gear 109 at the end thereof to rotate, and drives a plurality of the primary planetary gears 104 in meshing with the input sun gear 109 to rotate on the respective fixed first planet carrier 103; since the first planet carrier 103 is fixed to the fixed flange plate 101, the rotation of the primary planetary gears 104 forces the power conversion ring gear 105 (through the first inner teeth 110 thereof) in meshing with the primary planetary gears 104 to rotate around the axis, and completes the first-stage speed reduction and torque increase; the rotating power conversion ring gear 105 in turn drives a plurality of the secondary planetary gears 106 to rotate through the second outer teeth 111 of the power conversion ring gear 105; at the same time, the secondary planetary gears 106 are also in meshing with the fixed ring gear 107 (through the third inner teeth 112 thereof) fixed to the inner side wall of the fixed flange plate 101, and the rotating secondary planetary gears 106 are forced to revolve around the input shaft center line under the constraint of the fixed ring gear 107, thereby driving the second planet carrier and the output flange plate 108 fixed thereto to rotate, and realizing the second-stage speed reduction. Finally, the power with reduced rotation speed and increased torque is stably output from the output flange plate 108.

[0024] The technical effect of the speed reducer assembly is that the input sun gear 109 drives the first-stage planetary gears 104, the first-stage planetary gears 104 drive the rotatable power conversion ring gear 105 to complete the first-stage speed reduction; the power conversion ring gear 105 simultaneously serves as the sun gear of the second stage, and the second outer teeth 111 of the power conversion ring gear 105 drive the second-stage planetary gears 106, and the rotating second-stage planetary gears 106 are forced to revolve around the input shaft center line under the constraint of the fixed ring gear 107, thereby driving the second planet carrier and the output flange plate 108 fixed thereto to rotate, and realizing the second-stage speed reduction. The above structure shares the same axial space for two-stage speed reduction, and the power conversion ring gear 105 as the core transmission member is connected in series for two stages, which significantly reduces the axial stacking thickness caused by the traditional series structure, and realizes the ultrathin and compact structure of the overall structure. Meanwhile, the first planet carrier 103 and the fixed ring gear 107 are directly fixed to the fixed flange plate 101, the second planet carrier forms stable rotation output through the output flange plate 108, the support rigidity of the entire transmission chain is high, the axial positions of the gears are constrained by the structure itself, thereby effectively inhibiting the axial movement problem that may occur in multi-stage transmission, and ensuring the stability and precision of transmission while realizing large speed reduction ratio.

[0025] Further, the inner wall of each primary planetary gear 104 and the outer wall of the mounting shaft of the corresponding first planet carrier 103 are provided with a first needle roller 113.

[0026] In the embodiment, the first needle roller 113 serves as a bearing, greatly reducing the friction resistance of the primary planetary gear 104 when rotating on the first planetary carrier 103, improving the transmission efficiency and smoothness of the first-stage reduction, and the thin structure helps to maintain the compact and ultra-thin design of the overall reducer.

[0027] Further, the second planetary carrier includes a rotating disc 114 and a plurality of connecting shafts 115. The rotating disc 114 is rotatably arranged on the fixed flange disc 101 and located on the side of the fixed ring gear 107 away from the output flange disc 108. The output flange disc 108 is fixedly provided with a plurality of mounting protrusions 116 on the side facing the rotating disc 114. The rotating disc 114 is uniformly provided with a plurality of fixed pins 117, each of which is connected to one of the mounting protrusions 116. The connecting shaft 115 is arranged between each adjacent pair of fixed pins 117. The outer part of each connecting shaft 115 is rotatably mounted with the secondary planetary gear 106.

[0028] In the embodiment, the rotating disc 114, the fixed pins 117, the mounting protrusions 116, and the output flange disc 108 are rigidly connected, forming a structurally stable second planetary carrier. This structure not only provides precise installation and support for the secondary planetary gears 106, ensuring synchronous movement of the plurality of secondary planetary gears 106, but also serves as the main body for torque bearing and transmission of the entire output end, with good structural rigidity and stable power output.

[0029] Further, the inner wall of each secondary planetary gear 106 and the outer wall of the corresponding connecting shaft 115 are provided with a second needle roller 118.

[0030] In the embodiment, the second needle roller 118 is used as a bearing, effectively reducing the friction of the secondary planetary gear 106 rotating around the connecting shaft 115, ensuring high efficiency and low loss of the second-stage reduction transmission, and its thin profile is consistent with the overall ultra-thin design goal.

[0031] Further, the surface of the power conversion ring gear 105 in contact with the fixed flange disc 101 and the surface of the power conversion ring gear 105 in contact with the output flange disc 108 are provided with a flat needle bearing 119.

[0032] In the embodiment, the flat needle bearing 119 allows the power conversion ring gear 105 to rotate smoothly and accurately relative to the fixed flange disc 101 and the output flange disc 108, serving as the core role of connecting the two-stage reduction and transmitting power, while minimizing the additional axial size increase caused by support.

[0033] Further, the side of the fixed ring gear 107 in contact with the rotating disc 114 and the side of the fixed ring gear 107 in contact with the output flange 108 are both provided with an annular groove 120, and the interior of each annular groove 120 is provided with a plurality of balls 121.

[0034] In this embodiment, the annular groove 120 and the balls 121 cooperate to provide extremely low friction resistance support for the rotation of the rotating disc 114 and the output flange 108 relative to the fixed ring gear 107, and on the other hand can effectively withstand the axial force generated during operation.

[0035] The above only discloses one preferred embodiment of the present application, of course cannot with this to limit the scope of the present application, those skilled in the art can understand that the implementation of all or part of the above-mentioned processes, and according to the equivalent changes made by the claims of the present application, still belong to the scope of the present application.

Claims

1. A speed reducer assembly, characterized in that, The device includes a fixed flange, an output shaft, multiple first planetary carriers, multiple first-stage planetary gears, a power conversion gear ring, multiple second-stage planetary gears, a second planetary carrier, a fixed gear ring, and an output flange. The output shaft is rotatably disposed at the center of the fixed flange. An input sun gear is disposed at one end of the output shaft that extends into the interior of the fixed flange. Multiple first planetary carriers are fixedly disposed on the fixed flange and evenly distributed around the input sun gear. Each first planetary carrier is rotatably mounted with one of the first-stage planetary gears, and all of the multiple first-stage planetary gears mesh with the input sun gear. The power conversion gear ring is rotatably disposed inside the fixed flange. The inner ring of the power conversion gear ring is provided with a first internal tooth, which meshes with a plurality of the first-stage planetary gears. The outer ring of the power conversion gear ring is provided with a second external tooth. The fixed flange is provided with a fixed gear ring on its inner sidewall, and a third internal tooth is provided on the inner sidewall of the fixed gear ring. The second planetary carrier is rotatably disposed inside the fixed flange. Multiple secondary planetary gears are rotatably mounted on the second planetary carrier. Each secondary planetary gear simultaneously meshes with the second external tooth and the third internal tooth. The output flange is fixedly disposed on the end face of the second planetary carrier.

2. The reducer assembly as described in claim 1, characterized in that, Each of the first-stage planetary gears has a first needle roller between its inner wall and the outer wall of the mounting shaft of the corresponding first planetary carrier.

3. The reducer assembly as described in claim 2, characterized in that, The second planetary carrier includes a rotating disk and multiple connecting shafts. The rotating disk is rotatably mounted on the fixed flange and located on the side of the fixed gear ring away from the output flange. Multiple mounting protrusions are fixedly provided on the side of the output flange facing the rotating disk. Multiple fixing pins are evenly arranged on the rotating disk. Each fixing pin is connected to one of the mounting protrusions. A connecting shaft is provided between every two adjacent fixing pins. The second-stage planetary gear is rotatably mounted on the outside of each connecting shaft.

4. The reducer assembly as described in claim 3, characterized in that, A second needle roller is provided between the inner wall of each of the secondary planetary gears and the outer wall of the corresponding connecting shaft.

5. The reducer assembly as described in claim 4, characterized in that, Both the side of the power conversion gear ring that contacts the fixed flange and the side of the power conversion gear ring that contacts the output flange are provided with flat needle roller bearings.

6. The reducer assembly as described in claim 5, characterized in that, The fixed gear ring has an annular groove on the side that contacts the rotating disk and on the side that contacts the output flange, and each annular groove contains a plurality of balls.

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