Planetary reducer and joint structure

Abstract

The utility model provides a planetary reducer and a joint structure. The planetary speed reducer comprises a shell, the sun gear is rotatably arranged in the shell; the planet gears are arranged in the circumferential direction of the sun gear and meshed with the sun gear; the first outer gear ring is connected with the shell, and the first outer gear ring is arranged on the outer side of the planet wheel in a sleeving mode and engaged with the planet wheel; and the second outer gear ring is rotatably arranged relative to the shell, the second outer gear ring is arranged on the outer side of the planet wheel in a sleeving mode and meshed with the planet wheel, and the first outer gear ring and the second outer gear ring are different in displacement coefficient so that the tooth numbers of the first outer gear ring and the second outer gear ring can be different. The planetary reducer solves the problems that in the prior art, a planetary reducer of a 3K structure and the like is high in machining difficulty and cost.

Description

TECHNICAL FIELD

[0001] The utility model relates to robot technical field, specifically, a kind of planetary reducer and joint structure. BACKGROUND

[0002] In the robot industry, collaborative robot arm, small industrial robot arm usually adopt harmonic reducer and planetary reducer system as main, and RV reducer and cycloidal pin gear reducer system is mainly scheme in heavy-duty robot arm with high torque demand.Usually, the selection of reducer also needs to be considered from motor rotor inertia, transmission ratio, friction loss, etc., and the ultimate goal is to maximize the efficiency of joint drive system. Considering that motor is usually more efficient at high speed, so the reducer of joint drive system usually adopts reducer with higher reduction ratio.

[0003] 3K configuration as a kind of output form of planetary reducer, compared with ordinary planetary gear has higher reduction ratio and relatively lower efficiency. But the current 3K configuration and other planetary reducers usually adopt multi-stage planetary gear structure, which makes its structure complex, and the processing difficulty and cost are greatly improved. SUMMARY

[0004] The main purpose of the utility model is to provide a kind of planetary reducer and joint structure, to solve the processing difficulty and cost problem of 3K configuration and other planetary reducers in prior art.

[0005] In order to achieve the above purpose, according to one aspect of the utility model, a kind of planetary reducer is provided, comprising: shell;Sun gear, sun gear is rotatably arranged in shell;A plurality of planetary gears, planetary gear is arranged along the circumference of sun gear and is engaged with sun gear;First outer gear, first outer gear is connected with shell, first outer gear is set on the outer side of planetary gear and is engaged with planetary gear;Second outer gear, second outer gear is rotatably arranged relative to shell, second outer gear is set on the outer side of planetary gear and is engaged with planetary gear, the displacement coefficient of first outer gear and second outer gear is different to make the tooth number of two different.

[0006] Further, the first outer gear is a non-modified gear, and the second outer gear is a modified gear.

[0007] Further, the first outer gear and the second outer gear are arranged along the axial direction of the planetary gear, and along the axial direction of the planetary gear, the axial length of the planetary gear is not less than the axial length of any one of the first outer gear and the second outer gear.

[0008] Further, the inner ring of the shell has a stepped structure, the planetary reducer further comprises a retaining ring and a bearing member, the retaining ring is arranged at the edge of the end face of the shell, at least a part of the second outer gear is rotatably clamped between the stepped structure and the retaining ring, and the bearing member is arranged between the retaining ring and the second outer gear.

[0009] Further, the planetary reducer further comprises an output portion located at the inner side of the blocking ring and connected with the second outer gear ring.

[0010] Further, the first outer gear ring and the second outer gear ring are respectively abutted with two step faces on two sides of the step structure.

[0011] Further, the planetary reducer further comprises a sun seat rotatably arranged in the housing and connected with the sun gear, and a planet carrier rotatably arranged in the housing and sleeved on the outer side of the sun seat, and the planet gear is rotatably connected with the planet carrier.

[0012] Further, the planetary reducer further comprises an auxiliary bearing arranged at least one of the sun seat and the planet carrier, and the planet carrier and the housing.

[0013] According to another aspect of the utility model, a joint structure is provided, which comprises: a first base; a second base, the first base and the second base are rotatably connected; the planetary reducer described above, the planetary reducer is arranged in the first base and / or the second base; a driving member, the driving member is drivingly connected with the planetary reducer and outputs torque to the outside through the planetary reducer, and an axis of relative rotation between the first base and the second base and an axis of the output torque of the planetary reducer form an included angle.

[0014] Further, the planetary reducer has an output end located at the second base, and the joint structure further comprises a detection member located at the output end and detecting the output state of the output end.

[0015] The technical scheme of the utility model, by adopting the structure of the first outer gear ring and the second outer gear ring, and the first outer gear ring and the second outer gear ring are engaged with the planet gear, the first outer gear ring and the second outer gear ring are designed to have different number of teeth through different variable coefficients, so that the planetary reducer can still achieve the performance effect of the traditional 3K configuration planetary reducer, since the scheme of the embodiment does not need multi-stage planetary gear, the processing difficulty and cost are greatly reduced, the difficulty of manufacturing a set of variable tooth ring is much less than that of manufacturing a double-layer planet gear with a fixed phase angle, especially in the laboratory test stage, the tooth ring, planet gear and sun gear can be processed by wire cutting slow wire. At the same time, the planetary reducer of the embodiment needs fewer parts, and can be quickly replaced by a similar reduction ratio scheme by replacing the variable tooth, so it has high reusability and replaceability in the early stage of joint system design. Overall, compared with the traditional 3K reducer, the scheme of the embodiment has the same performance, lower cost and more variable reduction scheme. BRIEF DESCRIPTION OF DRAWINGS

[0016] The drawings accompanying the specification of this application serve to provide further understanding of the present application, the illustrative embodiments of the present application and its description serve to explain the present application, and do not constitute an improper limitation on the present application. In the drawings:

[0017] Figure 1 A structural schematic diagram of the planetary reducer of the present application is shown;

[0018] Figure 2 An exploded view of the planetary reducer in Figure 1 is shown;

[0019] Figure 3 A sectional view of the planetary reducer in Figure 1 is shown;

[0020] Figure 4 Another direction sectional view of the planetary reducer in Figure 1 is shown;

[0021] Figure 5 A structural schematic diagram of the joint structure of the present application is shown;

[0022] Figure 6 A sectional view of the joint structure in Figure 5 is shown.

[0023] Among the above drawings, the following reference signs are included:

[0024] 10, housing; 20, sun gear; 30, planet gear; 40, first outer gear ring; 50, second outer gear ring; 60, retainer; 70, bearing member; 80, output; 90, sun seat; 100, planet carrier; 110, auxiliary bearing; 120, first base; 130, second base; 140, driving member; 150, detecting member. DETAILED DESCRIPTION

[0025] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict. The present application will be described in detail below with reference to the drawings and in combination with the embodiments.

[0026] It should be noted that, unless otherwise specified, all technical and scientific terms used in the present application have the same meaning as generally understood by those skilled in the art to which the present application belongs.

[0027] In the utility model, in the case that no opposite statement is made, the orientation words such as ''up, down, top, bottom'' used are usually in the direction shown in the drawing, or in the vertical, perpendicular or gravity direction of the components themselves; similarly, for the convenience of understanding and description, ''inner, outer'' refers to the inner and outer relative to the contour of the components themselves, but the above orientation words are not used to limit the utility model.

[0028] In order to solve the machining difficulty and high cost of the 3K configuration planetary reducer in the prior art, the utility model provides a planetary reducer and joint structure.

[0029] As shown in a kind of planetary reducer in Figures 1 to 4 , including shell 10, sun gear 20, multiple planetary gears 30, first outer gear 40 and second outer gear 50, sun gear 20 is rotatably arranged in shell 10;Planetary gears 30 are arranged along the circumference of sun gear 20 and mesh with sun gear 20;First outer gear 40 is connected with shell 10, first outer gear 40 is set on the outer side of planetary gears 30 and mesh with planetary gears 30;Second outer gear 50 is rotatably arranged relative to shell 10, second outer gear 50 is set on the outer side of planetary gears 30 and mesh with planetary gears 30, and the modification coefficient of first outer gear 40 and second outer gear 50 is different to make the tooth number of two different.

[0030] The embodiment is by adopting the structural form of the two outer gears of first outer gear 40 and second outer gear 50, and first outer gear 40 and second outer gear 50 are all meshed with planetary gears 30, and first outer gear 40 and second outer gear 50 are designed into the form of different tooth number by the difference of modification coefficient between first outer gear 40 and second outer gear 50, so that the planetary reducer can still reach the performance effect of traditional 3K configuration planetary reducer, since the scheme of the embodiment does not need multi-stage planetary gear, so its machining difficulty and cost are greatly reduced, the difficulty of manufacturing a set of modification gear is much less than manufacturing a double-layer planetary gear with fixed phase angle, especially in the laboratory test stage, the gear, planetary gears 30 and sun gear 20 and other components can be machined by wire cutting slow wire feeding. Meanwhile, the planetary reducer of the embodiment needs fewer parts, and can be quickly replaced by a similar reduction ratio scheme by replacing the modification gear, so it has high reusability and replaceability in the early stage of joint system design. Overall, compared with traditional 3K reducer, the scheme of the embodiment has the same performance, more affordable cost and more variable reduction scheme.

[0031] As shown in a kind of planetary reducer in Figure 4As shown, in this embodiment, the first external gear ring 40 is a non-displaced gear ring, and the second external gear ring 50 is a displaced gear ring. Both non-displaced and displaced gear rings are relative to the meshing planetary gears 30. That is, the first external gear ring 40 is a non-displaced gear ring normally meshed with the planetary gears 30, while the second external gear ring 50 is a displaced gear ring with teeth that have changed relative to the planetary gears 30, thereby achieving differential gear reduction and a high reduction ratio in the planetary reducer. In this embodiment, the displaced gear ring reduces the number of teeth after displacement. In this embodiment, three teeth are reduced, thereby generating output torque during the rotation of the planetary carrier 100. Of course, the specific external gear ring that uses displacement and the specific number of displaced teeth can be adjusted as needed, and are not limited to the settings described above in this embodiment. As long as the displacement coefficients of the first external gear ring 40 and the second external gear ring 50 are different, resulting in different numbers of teeth and different meshing states with the planetary gears 30, thus producing differential gear reduction output, it is acceptable.

[0032] It should be noted that in this embodiment, the "outer" in the first external gear ring 40 and the second external gear ring 50 refers to the fact that they are sleeved on the outside of the planetary gear 30. The first external gear ring 40 and the second external gear ring 50 actually have internal teeth, and the meshing with the planetary gear 30 is achieved through the internal teeth.

[0033] like Figure 3 As shown, in this embodiment, since both the first external gear ring 40 and the second external gear ring 50 are meshed with the planetary gear 30, the first external gear ring 40 and the second external gear ring 50 are arranged along the axial direction of the planetary gear 30, and the planetary gear 30 has a certain length along its axial direction. The axial length of the planetary gear 30 is not less than the axial length of either the first external gear ring 40 or the second external gear ring 50, thereby ensuring that the first external gear ring 40 and the second external gear ring 50 can simultaneously mesh and transmit with different segments of the planetary gear 30 along its axial direction.

[0034] In this embodiment, three planetary gears 30 are provided. The three planetary gears 30 are arranged at equal intervals on the outer periphery of the sun gear 20. The first external gear ring 40 and the second external gear ring 50 are both integrally fitted on the outside of the three planetary gears 30 and simultaneously mesh with the three planetary gears 30.

[0035] like Figure 2As shown, in the present embodiment, the housing 10 comprises a ring part and a ring cover, wherein the sun gear 20, the planet wheel 30 and other components are accommodated in the ring part, the ring cover covers the end of the ring part, and the circumferential edge portion space of the end is shielded, and the other end of the ring part can be used for connecting the components output externally. Wherein, a step structure protruding inward is arranged on the inner ring side wall of the ring part, the planetary reducer further comprises a check ring 60 and a bearing part 70, the check ring 60 is arranged at the end face edge of the ring part, and the check ring 60 and the ring cover are respectively located on the opposite sides of the ring part, and at least a part of the second outer gear 50 is rotatably clamped between the step structure and the check ring 60, so that the effect of installing the second outer gear 50 in the housing 10 can be realized by the cooperation between the check ring 60 and the step structure. At the same time, since the second outer gear 50 rotates relative to the housing 10, the bearing part 70 is arranged between the check ring 60 and the second outer gear 50, and the bearing part 70 can adopt a forked roller bearing and other components, so as to realize the smooth rotation of the second outer gear 50.

[0036] The planetary reducer of the present embodiment further comprises an output part 80, which can be an output flange structure, and the output part 80 is located on the inner side of the check ring 60, so that the output part 80 can be connected with the second outer gear 50 through bolts and other components, so that the second outer gear 50 can realize the effect of external transmission connection through the output part 80. When installing, the second outer gear 50 is pressed into the inner side part of the bearing part 70 before the bearing part 70 is fixed, and is fixed between the output part 80 through screws. After the above assembly is completed, the upper half of the bearing part 70 locks the housing 10 and the check ring 60 through screws to fix the bearing part 70.

[0037] In the present embodiment, the check ring 60, the bearing part 70 and the second outer gear 50 are located on the same side of the step structure, and the first outer gear 40 and the ring cover are located on the other side of the step structure, and the first outer gear 40 is clamped between the other side of the step structure and the ring cover. When installing, the first outer gear 40 and the second outer gear 50 respectively abut against the two step surfaces on the opposite sides of the step structure, so as to respectively realize the installation of the components on the two sides of the step structure. The installation between the components of the present embodiment can all adopt the form of screws and installation holes, that is, installation holes are opened on the components to be connected, and screws are arranged in the installation holes to realize installation and fixation.

[0038] In the embodiment, the planetary reducer further comprises a sun seat 90 and a planet carrier 100, the sun seat 90 is rotatably arranged in the housing 10, and the sun gear 20 is connected with the sun seat 90; the planet carrier 100 is rotatably arranged in the housing 10 and is sleeved outside the sun seat 90, and the planet gear 30 is rotatably connected with the planet carrier 100. Through the sun seat 90 and the planet carrier 100, on the one hand, the installation of the sun gear 20 and the planet gear 30 can be realized, and on the other hand, the transmission matching relationship between the sun gear 20 and the planet gear 30 can be ensured, and the overall structural stability of the planetary reducer can be ensured.

[0039] The planetary reducer of the embodiment further comprises an auxiliary bearing 110, which can be a common roller bearing, and the auxiliary bearing 110 is arranged at least one of between the sun seat 90 and the planet carrier 100 and between the planet carrier 100 and the housing 10. In the embodiment, the auxiliary bearing 110 is arranged between the sun seat 90 and the planet carrier 100 and between the planet carrier 100 and the housing 10, which can support the housing 10, the planet carrier 100 and the sun gear 20 from outside to inside, and can also ensure smooth rotation of the housing 10, the planet carrier 100 and the sun gear 20.

[0040] The sun seat 90 of the embodiment comprises two parts, namely a first seat body and a second seat body, wherein the first seat body and the second seat body are located at the two end faces of the sun gear 20 and are connected together, and the first seat body and the second seat body are located on the two sides of the center of the ring part. The first seat body is closer to the end cover than the second seat body, the planet carrier 100 is located outside the first seat body, and the auxiliary bearing 110 is arranged between the first seat body, the planet carrier 100 and the inner wall of the end cover. The second seat body is located at the inner ring of the output part 80, and the auxiliary bearing 110 is arranged between the second seat body and the output part 80, so that the two ends of the sun gear 20 are installed and supported by the seat body and the auxiliary bearing 110, and the overall structure of the planetary reducer is more stable. During installation, after the output part 80 and the bearing part 70 are installed, the output part 80 is fixed outside the second seat body through the auxiliary bearing 110, then the end cover, the planet carrier 100, the second seat body and the auxiliary bearing 110 therebetween are assembled together, and finally the second seat body is connected with the end face of the sun gear 20 through a screw.

[0041] The sun gear 20 of the embodiment is provided with an axial through hole at the center thereof, which can be used for passing the center shaft and realizing transmission matching, and can also be used for wiring, so that the wiring inside the robot can be realized more conveniently.

[0042] As Figure 5 And Figure 6 As shown in the drawings, the embodiment also provides a joint structure, which is mainly used on a robot and serves as a joint of the robot. The joint structure comprises a first base 120, a second base 130, the planetary reducer and a driving member 140. The first base 120 is rotatably connected with the second base 130. The planetary reducer is arranged in the first base 120 and / or the second base 130. The driving member 140 is drivingly connected with the planetary reducer and outputs torque through the planetary reducer. An axis of relative rotation between the first base 120 and the second base 130 forms an angle with an axis of the output torque of the planetary reducer. In this way, the overall structure of the joint structure is simplified by the structural design of the planetary reducer, and the complexity of the structure, the processing difficulty and the processing cost are greatly reduced, thereby facilitating the reduction of the manufacturing cost of the robot.

[0043] The first base 120 and the second base 130 of the embodiment are rotatably matched with each other, and the rotation axis therebetween is the first axis. Taking the first base 120 as the basic component and the planetary reducer being mainly arranged on the second base 130 as an example, the output end of the planetary reducer is located at the end of the second base 130, the rotation axis of the output end of the planetary reducer is the second axis, and the first axis and the second axis are vertically arranged in the embodiment. The driving member 140 is arranged in the first base 120, and a cylindrical gear or other transmission component can be arranged between the driving member 140 and the planetary reducer. The driving member 140 is drivingly connected with the planetary reducer through the transmission component, so as to realize the cooperation of the driving member 140 and the planetary reducer in the first base 120 and the second base 130 and realize the transmission of the torque to the planetary reducer for torque output.

[0044] The planetary reducer of the embodiment has the output end located at the second base 130, and the joint structure further comprises a detection member 150, which can be a magnetic encoder or the like. The detection member 150 is located at the output end, so as to detect the output state of the output end and ensure the real-time monitoring of the state of the joint structure.

[0045] It should be noted that the plurality of in the above embodiment means at least two.

[0046] From the above description, it can be seen that the above-mentioned embodiments of the utility model realize the following technical effects:

[0047] 1. The machining difficulty and cost of the 3K configuration planetary reducer in the prior art are solved.

[0048] 2. No need for multi-stage planetary gears, thus greatly reducing the difficulty and cost of processing, and the difficulty of manufacturing a set of displacement gear rings is much less than that of manufacturing a double-layer planetary gear with a fixed phase angle, especially in the laboratory test stage, the gear ring, planetary gear and sun gear and other components can be processed by wire cutting slow wire;

[0049] 3. Fewer parts are required, and similar reduction ratio schemes can be quickly replaced by replacing the displacement teeth, thus having high reusability and replaceability in the early stage of joint system design;

[0050] 4. Compared with the traditional 3K reducer, the planetary reducer of the embodiment has the same performance, lower cost and more variable reduction scheme.

[0051] Obviously, the above-described embodiments are only a part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor should belong to the scope of protection of the present application.

[0052] It should be noted that the terms used herein are only for the purpose of describing specific embodiments, and are not intended to limit the exemplary embodiments according to the present application. As used herein, the singular form is intended to include the plural form unless the context clearly indicates otherwise, and it should be understood that when the terms "comprise" and / or "include" are used in the specification, there is a feature, step, work, device, component and / or combination thereof.

[0053] It should be noted that the terms "first", "second" and the like in the specification and claims of the present application and the above-described drawings are used to distinguish similar objects, and do not necessarily describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein.

[0054] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. For those skilled in the art, the present application can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A planetary reducer, characterized in that, include: Outer shell (10); A sun gear (20) is rotatably disposed within the housing (10); Multiple planetary gears (30) are arranged circumferentially along the sun gear (20) and mesh with the sun gear (20); The first external gear ring (40) is connected to the outer shell (10) and is sleeved on the outside of the planetary gear (30) and meshes with the planetary gear (30). The second external gear ring (50) is rotatably disposed relative to the outer shell (10). The second external gear ring (50) is sleeved on the outside of the planetary gear (30) and meshes with the planetary gear (30). The displacement coefficients of the first external gear ring (40) and the second external gear ring (50) are different so that the number of teeth of the two are different.

2. The planetary reducer according to claim 1, characterized in that, The first external gear ring (40) is a non-displaced gear ring, and the second external gear ring (50) is a displaced gear ring.

3. The planetary reducer according to claim 1, characterized in that, The first external gear ring (40) and the second external gear ring (50) are arranged along the axial direction of the planetary gear (30), and the axial length of the planetary gear (30) is not less than the axial length of either the first external gear ring (40) or the second external gear ring (50).

4. The planetary reducer according to claim 1, characterized in that, The inner ring of the housing (10) has a stepped structure. The planetary reducer also includes a retaining ring (60) and a bearing (70). The retaining ring (60) is disposed at the edge of the end face of the housing (10). At least a portion of the second external gear ring (50) is rotatably clamped between the stepped structure and the retaining ring (60). The bearing (70) is disposed between the retaining ring (60) and the second external gear ring (50).

5. The planetary reducer according to claim 4, characterized in that, The planetary reducer also includes an output section (80), which is located inside the retaining ring (60) and connected to the second external gear ring (50). The second external gear ring (50) is externally driven through the output section (80).

6. The planetary reducer according to claim 4, characterized in that, The first external gear ring (40) and the second external gear ring (50) respectively abut against the two stepped surfaces on opposite sides of the stepped structure.

7. The planetary reducer according to claim 1, characterized in that, The planetary reducer also includes: A sun seat (90) is rotatably disposed within the outer casing (10), and a sun wheel (20) is connected to the sun seat (90); Planetary carrier (100), which is rotatably disposed inside the outer shell (10) and sleeved on the outside of the sun seat (90), wherein the planetary gear (30) is rotatably connected to the planetary carrier (100).

8. The planetary reducer according to claim 7, characterized in that, The planetary reducer also includes an auxiliary bearing (110), which is provided at least once between the sun seat (90) and the planet carrier (100), and between the planet carrier (100) and the outer casing (10).

9. A joint structure, characterized in that, include: First base (120); The second base (130) is rotatably connected to the first base (120); The planetary reducer according to any one of claims 1 to 8, wherein the planetary reducer is disposed within the first base (120) and / or the second base (130); A drive unit (140) is connected to the planetary reducer and outputs torque through the planetary reducer. The axis of relative rotation between the first base (120) and the second base (130) forms an angle with the axis of the output torque of the planetary reducer.

10. The joint structure according to claim 9, characterized in that, The planetary reducer has an output end located at the second base (130), and the joint structure further includes a detection element (150) located at the output end and detecting the output state of the output end.

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