Planetary gear type rotation limiting mechanism

Abstract

The utility model discloses a planetary gear type rotary limiting mechanism, output shaft rotates and passes through the deceleration casing, and the one end of output shaft is equipped with first gear, the one end of planet carrier is fixedly installed in the deceleration casing, and the other end of planet carrier rotatably installs the second gear of meshing with first gear, the ring groove of deceleration casing rotatably installs the outer circumferential wall of gear ring, and the inner circumferential wall of gear ring is engaged with planetary gear, and the abutting boss of gear ring is equipped with the movable abutting of limiting boss. Output shaft is coaxial connection with input shaft, and input shaft is connected with steering wheel, when the steering wheel rotates, through the drive output shaft rotation of input shaft, the meshing of output shaft through first gear and second gear, the meshing drive gear ring rotation of second gear and gear ring, until the abutting boss on gear ring and limiting boss contact, limit gear ring to continue to rotate, and then through the reverse locking output shaft and steering wheel of first gear and second gear, reach the purpose of limiting the rotation circle number of steering wheel.

Description

Technical Field

[0001] This utility model relates to the field of automotive steering technology, specifically to a planetary gear-type rotary limiting mechanism. Background Technology

[0002] With the development of steer-by-wire technology in automobiles, the mechanical intermediate shaft connecting the steering wheel and steering gear in traditional steering systems has been eliminated. Steering commands are now transmitted between the steering column and steering gear solely through electrical signals. While steer-by-wire systems enhance design flexibility and driving experience, the lack of mechanical hard-stop functionality introduces new safety hazards: when the vehicle loses power or the controller software malfunctions, the steering wheel loses its electronic limit constraint and can rotate without limit, leading to uncontrolled steering wheel angles and a high risk of accidents. This is because in mechanical steering systems, the physical limits of the steering gear can be transmitted back to the steering wheel via the intermediate shaft (e.g., steering gear rack limit → intermediate shaft torque transmission → steering wheel lock). However, because the mechanical connection is eliminated in steer-by-wire systems, the physical limits of the steering gear cannot be transmitted back to the steering wheel.

[0003] Some solutions attempt to limit the number of steering wheel turns by adding electronic sensors or software algorithms, but these rely on the power and control system and are still at risk of failure in the event of power failure, system malfunction, or electromagnetic interference, and cannot provide a reliable mechanical hard limit. Utility Model Content

[0004] To address the aforementioned technical problems, this utility model proposes a planetary gear-type rotary limiting mechanism. The output shaft drives the gear ring to rotate through the meshing of the first gear and the second gear, and the meshing of the second gear and the gear ring, until the abutment boss on the gear ring contacts the limiting boss, thus limiting the gear ring from continuing to rotate.

[0005] The technical solution adopted by this utility model is as follows: A planetary gear rotary limiting mechanism, characterized in that it includes a reduction housing, an output shaft, a planetary carrier, and a gear ring; the reduction housing is provided with a limiting boss and an annular groove; the output shaft rotatably passes through the reduction housing, and a first gear is provided at one end of the output shaft; one end of the planetary carrier is fixedly installed on the reduction housing, and a second gear that meshes with the first gear is rotatably installed at the other end of the planetary carrier; the outer peripheral wall of the gear ring is rotatably installed in the annular groove of the reduction housing, the inner peripheral wall of the gear ring meshes with the planetary gear, and the gear ring is provided with an abutment boss that movably abuts against the limiting boss.

[0006] Optionally, the planetary carrier includes a support plate and multiple support columns, which are spaced apart circumferentially along the support plate. The number of second gears is multiple, and the multiple second gears are rotatably connected to the multiple support columns in a one-to-one correspondence. The multiple second gears are respectively meshed with the first gear. The reduction housing is provided with a first through hole that is interference-fitted with the support column, and the support plate is provided with a second through hole for the output shaft to pass through.

[0007] Optionally, the second gear is rotatably mounted on the end of the support column away from the reduction gear housing via the first bearing.

[0008] Optionally, the diameter of the output shaft is smaller than the diameter of the second through hole.

[0009] Optionally, the deceleration housing includes a deceleration body and a limiting housing circumferentially disposed on the end face of the deceleration housing. The limiting housing has a limiting boss on its inner peripheral wall. The end face of the deceleration housing has a first through hole and a third through hole for the output shaft to pass through. The first through hole is distributed circumferentially along the third through hole.

[0010] Optionally, grease is applied between the outer peripheral wall of the gear ring and the annular groove, or a second bearing is provided between the outer peripheral wall of the gear ring and the annular groove.

[0011] Optionally, the inner peripheral wall of the gear ring is provided with gear teeth that mesh with the second gear, and the end of the gear ring facing the deceleration body is provided with the abutting boss; or the end face of the limiting housing away from the deceleration body is provided with an axially extending limiting boss, the gear ring protrudes out of the limiting housing to form a protruding end, and the side wall of the protruding end is provided with the abutting boss.

[0012] Optionally, the output shaft includes a first shaft and a second shaft connected to the first shaft. The first shaft is provided with the first gear at the end away from the second shaft, and the end of the first shaft near the second shaft is a smooth shaft with a diameter smaller than the diameter of the second through hole.

[0013] Optionally, it may also include a fixing cover, which is press-fitted to the outer peripheral wall of the limiting housing, or the fixing cover is connected to the outer peripheral wall of the limiting housing by a snap fastener, or the fixing cover is connected to the outer peripheral wall of the limiting housing by a thread.

[0014] The beneficial effects of this invention are as follows: the output shaft and input shaft are coaxially connected, and the input shaft is connected to the steering wheel. When the steering wheel rotates, the input shaft drives the output shaft to rotate. The output shaft, through the meshing of the first gear and the second gear, and the meshing of the second gear and the gear ring, drives the gear ring to rotate until the abutment boss on the gear ring contacts the limiting boss, restricting the gear ring from continuing to rotate. Furthermore, the first and second gears lock the output shaft and steering wheel in opposite directions, thus limiting the number of rotations of the steering wheel. Multiple second gears and first gears are arranged in a planetary configuration, evenly distributing the input torque to multiple meshing points and reducing stress distribution. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the planetary gear rotary limiting mechanism proposed in an embodiment of the present invention;

[0016] Figure 2An exploded view of the planetary carrier, second gear, and output shaft of the planetary gear rotary limiting mechanism proposed in this embodiment of the utility model.

[0017] Figure 3 This is an exploded view of the gear ring and the reduction housing of the planetary gear rotary limiting mechanism proposed in this embodiment of the utility model.

[0018] Figure 4 This is a schematic diagram showing the cooperation between the fixed cover and the reduction housing of the planetary gear type rotary limiting mechanism proposed in this embodiment of the utility model.

[0019] The markings in the attached figures are as follows: 1. Reduction housing; 11. Limiting boss; 12. Annular groove; 13. Reduction body; 14. Limiting housing; 15. First through hole; 16. Third through hole; 2. Output shaft; 21. First gear; 22. Smooth shaft; 23. Second shaft; 3. Planetary carrier; 31. Support plate; 311. Second through hole; 32. Support column; 4. Gear ring; 41. Gear tooth; 42. Abutment boss; 5. Second gear; 6. Fixed cover; 7. Input shaft; 8. Steering wheel. Detailed Implementation

[0020] The present application will now be described in further detail with reference to the accompanying drawings and embodiments.

[0021] like Figures 1 to 4 As shown, this embodiment discloses a planetary gear rotary limiting mechanism, including a reduction housing 1, an output shaft 2, a planetary carrier 3, and a gear ring 4. The reduction housing 1 is provided with a limiting boss 11 and an annular groove 12. The output shaft 2 rotates through the reduction housing 1, and a first gear 21 is provided at one end of the output shaft 2. One end of the planetary carrier 3 is fixedly installed on the reduction housing 1, and a second gear 5 that meshes with the first gear 21 is rotatably installed at the other end of the planetary carrier 3. The outer peripheral wall of the gear ring 4 is rotatably installed in the annular groove 12 of the reduction housing 1, and the inner peripheral wall of the gear ring 4 meshes with the second gear 5. The gear ring 4 is provided with an abutment boss 42 that moves against the limiting boss 11. Output shaft 2 is coaxially connected to input shaft 7, and input shaft 7 is connected to steering wheel 8. When steering wheel 8 rotates, input shaft 7 drives output shaft 2 to rotate. Output shaft 2, through the meshing of first gear 21 and second gear 5, and the meshing of second gear 5 and gear teeth 41, drives gear ring 4 to rotate until the abutment boss 42 on gear ring 4 contacts the limiting boss 11, restricting gear ring 4 from continuing to rotate. Furthermore, the first gear 21 and second gear 5 lock output shaft 2 and steering wheel 8 in the opposite direction, achieving the purpose of limiting the number of rotations of steering wheel 8. In other embodiments, planetary carrier 3 is rotatably mounted on reduction housing 1, and second gear 5 is fixedly connected to planetary carrier 3.

[0022] like Figure 2As shown, the planetary carrier 3 includes a support plate 31 and multiple support columns 32. The multiple support columns 32 are spaced apart circumferentially along the support plate 31. There are multiple second gears 5, each rotatably connected to one of the support columns 32, and each second gear 5 meshes with a first gear 21. The reduction housing 1 has a first through hole 15 that is interference-fitted with the support column 32, and the support plate 31 has a second through hole 311 through which the output shaft 2 passes. The multiple second gears 5 and the first gear 21 are arranged in a planetary configuration, evenly distributing the input torque to multiple meshing points and reducing stress distribution.

[0023] In this embodiment, the second gear 5 is rotatably mounted on the end of the support column 32 away from the reduction housing 1 via a first bearing. The inner ring of the first bearing is fixedly connected to the outer peripheral wall of the support column 32, and the outer ring of the first bearing is fixedly connected to the inner wall of the second gear 5.

[0024] In this embodiment, the diameter of the output shaft 2 is smaller than the diameter of the second through hole 311. This avoids interference from the planetary carrier 3 on the rotation of the output shaft 2.

[0025] like Figure 3 As shown, the reduction housing 1 includes a reduction body 13 and a limiting housing 14 circumferentially disposed on the end face of the reduction housing 1. The limiting housing 14 has a limiting boss 11 on its inner peripheral wall. The end face of the reduction housing 1 has a first through hole 15 and a third through hole 16 for the output shaft 2 to pass through. The first through hole 15 is distributed circumferentially along the third through hole 16. The reduction body 13 and the limiting housing 14 can be integrally formed by die casting, or the limiting housing 14 can be mounted on the reduction body 13 by screws. The first through hole 15 and the third through hole 16 are not interconnected.

[0026] In this embodiment, grease is applied between the outer peripheral wall of the gear ring 4 and the annular groove 12. In other embodiments, a second bearing may be provided between the outer peripheral wall of the gear ring 4 and the annular groove 12, allowing the gear ring 4 and the annular groove 12 to rotate relative to each other.

[0027] like Figure 3 As shown, in this embodiment, the inner peripheral wall of the gear ring 4 is provided with gear teeth 41 that mesh with the second gear 5, and the end of the gear ring 4 facing the deceleration body 13 is provided with the abutting boss 42; in other embodiments, the end face of the limiting housing 14 away from the deceleration body 13 is provided with an axially extending limiting boss 11, the gear ring 4 protrudes out of the limiting housing 14 to form a protruding end, and the side wall of the protruding end is provided with the abutting boss 42.

[0028] like Figure 2As shown, the output shaft 2 includes a first shaft body and a second shaft body 23 connected to the first shaft body. The first gear 21 is located at the end of the first shaft body away from the second shaft body 23, and a smooth shaft 22 is located at the end of the first shaft body near the second shaft body 23. The diameter of the smooth shaft 22 is smaller than the diameter of the second through hole 311. The second shaft body 23 is used to connect to the input shaft 7. The surface of the smooth shaft 22 has a smooth structure, and the length of the smooth shaft 22 can be greater than the axial length of the second through hole 311 to avoid interference between the first gear 21, the second shaft body 23, and the planetary carrier 3. The second shaft body 23 can be rotatably connected to the third through hole 16 of the reduction body 13 of the reduction housing 1 via a bearing.

[0029] like Figure 4 As shown, it also includes a fixing cover 6, which is press-fitted to the outer peripheral wall of the limiting housing 14, or the fixing cover 6 is connected to the outer peripheral wall of the limiting housing 14 by a snap fastener, or the fixing cover 6 is connected to the outer peripheral wall of the limiting housing 14 by a thread.

[0030] It is understood that the specific embodiments described above are merely for explaining the relevant utility model and not for limiting the utility model. It should also be noted that, for ease of description, only the parts related to the utility model are shown in the accompanying drawings. Multiple technical solutions in the same embodiment, as well as multiple technical solutions in different embodiments, can be arranged and combined to form new technical solutions that do not contradict or conflict with each other. All equivalent structural transformations made based on the content of this utility model specification and drawings, directly or indirectly applied to other related technical fields, are similarly included within the protection scope of this utility model.

Claims

1. A planetary gear type rotary limiting mechanism, characterized in that, Includes the reduction gear housing, output shaft, planetary carrier, and ring gear: The deceleration housing is provided with a limiting boss and an annular groove; The output shaft rotates through the reduction housing, and a first gear is provided at one end of the output shaft; One end of the planetary carrier is fixedly installed on the reduction housing, and the other end of the planetary carrier is rotatably installed with a second gear that meshes with the first gear. The outer peripheral wall of the gear ring is rotatably installed in the annular groove of the reduction housing, the inner peripheral wall of the gear ring meshes with the planetary gear, and the gear ring is provided with an abutment boss that moves against the limiting boss.

2. The planetary gear rotary limiting mechanism according to claim 1, characterized in that, The planetary carrier includes a support plate and multiple support columns, which are spaced apart circumferentially along the support plate. There are multiple second gears, which are rotatably connected to the multiple support columns in a one-to-one correspondence, and the multiple second gears mesh with the first gear respectively. The reduction housing is provided with a first through hole that is interference-fitted with the support column, and the support plate is provided with a second through hole for the output shaft to pass through.

3. The planetary gear rotary limiting mechanism according to claim 2, characterized in that, The second gear is rotatably mounted on the end of the support column away from the reduction gear housing via the first bearing.

4. The planetary gear rotary limiting mechanism according to claim 2, characterized in that, The diameter of the output shaft is smaller than the diameter of the second through hole.

5. The planetary gear rotary limiting mechanism according to claim 2, characterized in that, The deceleration housing includes a deceleration body and a limiting housing circumferentially disposed on the end face of the deceleration housing. The limiting housing has a limiting boss on its inner peripheral wall. The end face of the deceleration housing has a first through hole and a third through hole for the output shaft to pass through. The first through hole is distributed circumferentially along the third through hole.

6. The planetary gear rotary limiting mechanism according to claim 1, characterized in that, The outer peripheral wall of the gear ring is coated with grease between the gear ring and the annular groove, or a second bearing is provided between the outer peripheral wall of the gear ring and the annular groove.

7. The planetary gear rotary limiting mechanism according to claim 1, characterized in that, The inner peripheral wall of the gear ring is provided with gear teeth that mesh with the second gear, and the end of the gear ring facing the deceleration body is provided with the abutting boss; or the end face of the limiting housing away from the deceleration body is provided with an axially extending limiting boss, the gear ring protrudes out of the limiting housing to form a protruding end, and the side wall of the protruding end is provided with the abutting boss.

8. The planetary gear rotary limiting mechanism according to claim 2, characterized in that, The output shaft includes a first shaft and a second shaft connected to the first shaft. The first gear is provided at the end of the first shaft away from the second shaft, and the smooth shaft is at the end of the first shaft close to the second shaft. The diameter of the smooth shaft is smaller than the diameter of the second through hole.

9. The planetary gear rotary limiting mechanism according to claim 1, characterized in that, It also includes a fixing cover, which is press-fitted to the outer peripheral wall of the limiting housing, or the fixing cover is connected to the outer peripheral wall of the limiting housing by a snap fastener, or the fixing cover is connected to the outer peripheral wall of the limiting housing by a thread.

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