CN113460293A - Damping-adjustable front wheel shimmy damper for small and medium-sized unmanned aerial vehicles - Google Patents
Damping-adjustable front wheel shimmy damper for small and medium-sized unmanned aerial vehicles Download PDFInfo
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- CN113460293A CN113460293A CN202010244172.9A CN202010244172A CN113460293A CN 113460293 A CN113460293 A CN 113460293A CN 202010244172 A CN202010244172 A CN 202010244172A CN 113460293 A CN113460293 A CN 113460293A
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- outer cylinder
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- unmanned aerial
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- 238000013016 damping Methods 0.000 claims abstract description 21
- 238000004519 manufacturing process Methods 0.000 abstract description 9
- 230000005540 biological transmission Effects 0.000 abstract description 5
- 238000012545 processing Methods 0.000 abstract description 4
- 238000012423 maintenance Methods 0.000 abstract description 3
- 238000013461 design Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000002238 attenuated effect Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000012938 design process Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 238000000034 method Methods 0.000 description 1
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Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64C—AEROPLANES; HELICOPTERS
- B64C25/00—Alighting gear
- B64C25/32—Alighting gear characterised by elements which contact the ground or similar surface
- B64C25/50—Steerable undercarriages; Shimmy-damping
- B64C25/505—Shimmy damping
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64C—AEROPLANES; HELICOPTERS
- B64C25/00—Alighting gear
- B64C25/32—Alighting gear characterised by elements which contact the ground or similar surface
- B64C25/50—Steerable undercarriages; Shimmy-damping
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T50/00—Aeronautics or air transport
- Y02T50/40—Weight reduction
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Aviation & Aerospace Engineering (AREA)
- Steering-Linkage Mechanisms And Four-Wheel Steering (AREA)
- Vehicle Body Suspensions (AREA)
Abstract
The invention discloses a damping-adjustable front wheel shimmy damper for small and medium-sized unmanned aerial vehicles, which comprises a connecting rod, a sliding rod, an outer cylinder, a first adjusting plug cover, a first spring, a first retainer ring, a second adjusting plug cover, a second spring and a second retainer ring. The connecting rod is in threaded connection with the sliding rod, the sliding rod penetrates into the outer barrel, the first spring and the second spring are arranged between the sliding rod and the outer barrel, the first check ring and the second check ring are arranged between the first spring and the second spring, and the first adjusting plug cover and the second adjusting plug cover are connected to the two ends of the outer barrel through threads. The shimmy damper eliminates a force transmission gap, can adjust forward/backward pre-damping, is convenient and quick to adjust, has a simple structure, is low in processing and manufacturing cost, small in size and light in weight, does not fill oil in a cylinder, does not have the oil leakage problem of the traditional oil shimmy damper, and reduces the manufacturing and maintenance cost.
Description
Technical Field
The invention relates to the technical field of unmanned aerial vehicles, in particular to a damping-adjustable front wheel shimmy damper for small and medium-sized unmanned aerial vehicles.
Background
Landing gear shimmy has long existed as a serious failure factor of an aircraft, and the mere dependence on strength and rigidity adjustment of the landing gear is not enough to prevent shimmy. Long-term practice has shown that mounting a special shimmy damper on the landing gear is the most effective means for preventing shimmy of the landing gear.
The shimmy damper is an essential component for preventing the shimmy of the landing gear, and how to achieve the shimmy damping requirement in the simplest and most efficient structural form and how to determine the damping characteristic of the shimmy damper is the most important problem in the design and manufacturing process of the shimmy damper. The front wheel shimmy damper of the domestic conventional unmanned aerial vehicle mostly adopts an oil liquid damping type, has a complex structure, high manufacturing process requirement, long debugging period and large volume and weight, and is only suitable for large-scale unmanned aerial vehicles. For small and medium-sized unmanned aerial vehicles, small-sized man-machine shimmy dampers are mostly adopted at present. However, when the unmanned aerial vehicle shimmy damper is applied to an unmanned aerial vehicle front wheel electric steering system, the problems that the load of a steering engine is increased, a force transmission gap cannot be eliminated and the like exist, and the unmanned aerial vehicle front wheel electric steering system cannot be well adapted to the front wheel electric steering system.
In order to meet the requirements of small-sized, light-weight, low-cost, low-maintenance and better-adaptive electric steering system of the front wheel shimmy damper of the small-sized and medium-sized unmanned aerial vehicle, the light-weight small-sized shimmy damper with adjustable damping, simple structure and low manufacturing cost is designed to become an urgent task in the current development of the small-sized and medium-sized unmanned aerial vehicle.
Disclosure of Invention
The invention aims to solve the technical problem that the existing unmanned aerial vehicle adopts a manned hydraulic shimmy damper to increase the load of a steering engine, cannot eliminate a force transmission gap and cannot be matched with a front wheel electric steering system, and provides an adjustable damping front wheel shimmy damper for small and medium-sized unmanned aerial vehicles.
The purpose of the invention is realized by the following technical scheme:
a damping-adjustable front wheel shimmy damper for small and medium-sized unmanned aerial vehicles comprises a connecting rod, a sliding rod, an outer barrel, a first adjusting plug cover, a first spring, a first retainer ring, a second adjusting plug cover, a second spring and a second retainer ring;
the outer cylinder is a hollow cylinder, the sliding rod penetrates into the outer cylinder, a gap is reserved between the outer cylinder and the sliding rod, the first spring and the second spring are arranged in the gap between the outer cylinder and the sliding rod, and the first adjusting plug cover and the second adjusting plug cover are connected with two ends of the outer cylinder to fixedly compress the first spring and the second spring in the outer cylinder; the inner wall of the outer barrel is provided with a convex inner ring, a first spring and a second spring are respectively arranged on two sides of the inner ring, a first check ring is arranged between the first spring and the inner ring, and a second check ring is arranged between the second spring and the inner ring; the sliding rod is a round rod with one end drilled with a hole, the connecting rod is screwed into the sliding rod through threads, and a convex outer ring is arranged on the outer wall of the sliding rod corresponding to the inner ring of the outer cylinder.
When the transmitted steering force does not exceed the pre-damping, the shimmy damper is a rigid body, and no force transmission gap exists; when impact occurs or shimmy occurs, the sliding rod drives the check ring to overcome the damping force of the spring to slide back and forth in the outer barrel, and meanwhile, the shimmy is quickly attenuated by the damping of the spring, so that the shimmy reduction effect is achieved. If the external impact is too large, the square springs are combined in a circle, and the shimmy damper is prevented from being damaged.
Furthermore, the threaded connection part of the connecting rod and the sliding rod is provided with an adjusting nut, and the overall length of the connecting rod and the sliding rod is controlled by adjusting the adjusting nut, so that the purpose of adjusting the length of the shimmy damper is achieved.
Furthermore, the first spring and/or the second spring are square springs, and when the square springs are stressed and are combined, the spring rings cannot be dislocated, so that two limit designs can be reduced, and the manufacturing and processing difficulty and cost are reduced.
Further, the sum of the heights of the inner ring of the outer cylinder and the outer ring of the sliding rod is equal to the size of a gap between the outer cylinder and the sliding rod.
Furthermore, the first adjusting plug cover and/or the second adjusting plug cover are connected to the two ends of the outer barrel through threads, and the pre-damping effect can be adjusted by adjusting the screwing degree of the plug covers.
Furthermore, one end of the connecting rod is provided with an earring connected with a steering rocker arm of the undercarriage, and the adjusting blanking cover II is provided with an earring connected with a steering engine rocker arm.
Compared with the prior art, the beneficial effects are:
according to the damping-adjustable front wheel shimmy damper of the small and medium-sized unmanned aerial vehicle, the front and rear pre-damping is not directly acted on the sliding rod through the arrangement of the first check ring, the second check ring and the inner ring of the inner wall of the outer cylinder, so that the sliding rod can slide forwards/backwards in the outer cylinder only when the steering force transmitted by the shimmy damper exceeds the forward/backward pre-damping, and a force transmission gap is thoroughly eliminated.
The damping element used by the invention adopts the square spring, and when the square spring is stressed and looped, each spring loop cannot be dislocated, so that two limit designs can be reduced, and the manufacturing and processing difficulty and cost are reduced. And the screwing degree of the plug cover can be adjusted through adjustment, so that the forward/backward pre-damping can be respectively adjusted, and the adjustment is convenient and fast.
The damping-adjustable front wheel shimmy damper for the small and medium-sized unmanned aerial vehicles is simple in structure, low in processing and manufacturing cost, small in size and light in weight, oil is not filled in a cylinder, the problem of oil leakage of the traditional oil shimmy damper is solved, and the manufacturing and maintenance cost is reduced.
Drawings
FIG. 1 is a block diagram of the present invention;
fig. 2 is a cross-sectional view of the structure of the present invention.
The device comprises a connecting rod 1, an adjusting nut 2, an adjusting plug cover I3, a spring I4, a retainer ring I5, an outer cylinder 6, a retainer ring II 7, a spring II 8, an adjusting plug cover II 9, a sliding rod 10, an earring I11 and an earring II 12.
Detailed Description
The following examples are further explained and illustrated, but the present invention is not limited in any way by the specific examples. Unless otherwise indicated, the methods and equipment used in the examples are conventional in the art and all materials used are conventional commercially available materials.
Example 1
The utility model provides a middle-size and small-size unmanned aerial vehicle adjustable damping front wheel shimmy damper, includes connecting rod 1, adjusts blanking cap 3, spring 4, retaining ring 5, urceolus 6, retaining ring two 7, spring two 8, adjusts blanking cap two 9 and slide bar 10.
The outer cylinder 6 is a hollow cylinder, the sliding rod 10 penetrates into the outer cylinder 6, a gap is reserved between the outer cylinder 6 and the sliding rod 10, the first square spring 4 and the second square spring 8 are arranged in the gap between the outer cylinder 6 and the sliding rod 10, the first adjusting blanking cap 3 and the second adjusting blanking cap 9 are connected with the two ends of the outer cylinder 6, the first square spring 4 and the second square spring 8 are fixedly compressed in the outer cylinder 6, and the second adjusting blanking cap 9 is provided with a second earring 12 connected with a steering engine rocker arm.
The inner wall of the outer barrel 6 is provided with a convex inner ring, the first spring 4 and the second spring 8 are respectively arranged on two sides of the inner ring, the first retainer ring 5 is arranged between the first spring 4 and the inner ring, and the second retainer ring 7 is arranged between the second spring 8 and the inner ring.
The sliding rod 10 is a round rod with one end drilled, a protruding outer ring is arranged on the outer wall of the sliding rod 10 corresponding to the inner ring of the outer cylinder 6, the connecting rod 1 is screwed into the sliding rod 10 through threads, and one end of the connecting rod 1 is provided with a first lug ring 11 connected with a steering rocker arm of the landing gear.
Example 2
According to the figures 1-2, the damping-adjustable front wheel shimmy damper for the small and medium-sized unmanned aerial vehicles comprises a connecting rod 1, an adjusting nut 2, an adjusting blanking cover I3, a square spring I4, a check ring I5, an outer cylinder 6, a check ring II 7, a square spring II 8, an adjusting blanking cover II 9 and a sliding rod 10.
The outer barrel 6 is a hollow barrel, the sliding rod 10 penetrates into the outer barrel, a gap is reserved between the outer barrel 6 and the sliding rod 10, a first square spring 4 and a second square spring 8 are arranged in the gap between the outer barrel 6 and the sliding rod 10, the first adjusting blanking cap 3 is used for fixing the first square spring 4 in the outer barrel 6 through threaded connection, the second adjusting blanking cap 9 is used for fixing and compressing the second square spring 8 in the outer barrel 6 through threaded connection, and an ear ring 12 connected with a steering engine rocker arm is arranged on the second adjusting blanking cap 9.
The inner wall of the outer barrel 6 is provided with a convex inner ring, a first square spring 4 and a second square spring 8 are respectively arranged on two sides of the inner ring, a first check ring 5 is arranged between the first square spring 4 and the inner ring, and a second check ring 7 is arranged between the second square spring 8 and the inner ring.
The sliding rod 10 is a round rod with one end drilled with a hole, a convex outer ring is arranged on the outer wall of the sliding rod 10 corresponding to the inner ring of the outer barrel 6, the outer ring of the outer wall of the sliding rod 10 is matched with the inner wall of the outer barrel 6 in a protruding mode, the connecting rod 1 is screwed into the sliding rod 10 through threads, an adjusting nut 2 is arranged at the threaded connection position, the whole length of the shimmy damper can be adjusted, and an earring 11 connected with a steering rocker arm of an undercarriage is arranged at one end of the connecting rod 1.
It should be understood that the above-described embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the claims of the present invention.
Claims (7)
1. A damping-adjustable front wheel shimmy damper for small and medium-sized unmanned aerial vehicles is characterized by comprising a connecting rod, a sliding rod, an outer cylinder, a first adjusting plug cover, a first spring, a first retainer ring, a second adjusting plug cover, a second spring and a second retainer ring;
the outer cylinder is a hollow cylinder, the sliding rod penetrates into the outer cylinder, a gap is reserved between the outer cylinder and the sliding rod, the first spring and the second spring are arranged in the gap between the outer cylinder and the sliding rod, the first adjusting plug cover and the second adjusting plug cover are connected with two ends of the outer cylinder, and the first spring and the second spring are fixed in the outer cylinder; the inner wall of the outer barrel is provided with a convex inner ring, a first spring and a second spring are respectively arranged on two sides of the inner ring, a first check ring is arranged between the first spring and the inner ring, and a second check ring is arranged between the second spring and the inner ring;
the sliding rod is a round rod with one end drilled with a hole, the connecting rod is screwed into the sliding rod through threads, and a convex outer ring is arranged on the outer wall of the sliding rod corresponding to the inner ring of the outer cylinder.
2. The adjustable damping front wheel shimmy damper for small and medium sized unmanned aerial vehicles according to claim 1, wherein the threaded connection of the connecting rod and the sliding rod is provided with an adjusting nut.
3. The adjustable damping front wheel shimmy damper of small and medium size unmanned aerial vehicle of claim 1, characterized in that the spring one and/or the spring two is/are square spring.
4. The adjustable damping front wheel shimmy damper for small and medium sized unmanned aerial vehicles according to claim 1, wherein the sum of the heights of the inner ring of the outer cylinder and the outer ring of the sliding rod is equal to the size of a gap between the outer cylinder and the sliding rod.
5. The adjustable damping front wheel shimmy damper of small and medium size unmanned aerial vehicle of claim 1, characterized in that the adjusting blanking cap I and/or the adjusting blanking cap II are connected to the two ends of the outer cylinder through threads.
6. The adjustable damping front wheel shimmy damper for small and medium sized unmanned aerial vehicles according to claim 1, wherein one end of the connecting rod is provided with an earring connected with a steering rocker arm of an undercarriage.
7. The adjustable damping front wheel shimmy damper of small and medium sized unmanned aerial vehicle as claimed in claim 1, wherein the second adjusting blanking cover is provided with an earring connected with a steering engine rocker arm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010244172.9A CN113460293B (en) | 2020-03-31 | 2020-03-31 | Adjustable damping front wheel shimmy damper of small and medium-sized unmanned aerial vehicle |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010244172.9A CN113460293B (en) | 2020-03-31 | 2020-03-31 | Adjustable damping front wheel shimmy damper of small and medium-sized unmanned aerial vehicle |
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| Publication Number | Publication Date |
|---|---|
| CN113460293A true CN113460293A (en) | 2021-10-01 |
| CN113460293B CN113460293B (en) | 2024-01-30 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010244172.9A Active CN113460293B (en) | 2020-03-31 | 2020-03-31 | Adjustable damping front wheel shimmy damper of small and medium-sized unmanned aerial vehicle |
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Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB503807A (en) * | 1937-11-30 | 1939-04-14 | Ribbesford Company Ltd | Improvements in or relating to landing gear for aircraft |
| US20090224100A1 (en) * | 2008-03-05 | 2009-09-10 | Goodrich Corporation | Shimmy damper for aircraft landing gear |
| CN201800917U (en) * | 2010-09-30 | 2011-04-20 | 湖南山河科技股份有限公司 | Anti-shimmy mechanism of landing wheel |
| CN202244082U (en) * | 2011-08-29 | 2012-05-30 | 湖南山河科技股份有限公司 | Shimmy damper for rotor wing of helicopter |
| CN103038538A (en) * | 2010-07-29 | 2013-04-10 | 梅西耶-道提股份有限公司 | Hydraulic shimmy damper for aircraft landing gear |
| CN103523218A (en) * | 2013-10-12 | 2014-01-22 | 中国航天空气动力技术研究院 | Unmanned plane damping-adjustable front-wheel shimmy-damper |
| CN107780744A (en) * | 2016-08-31 | 2018-03-09 | 赵芬 | Angle positioning and self-closing hinge can be adjusted |
| RU2648483C1 (en) * | 2016-09-19 | 2018-03-26 | Олег Савельевич Кочетов | Combined vibration isolator |
| CN107878738A (en) * | 2016-09-29 | 2018-04-06 | 赛峰起落架系统公司 | It is equipped with the aircraft landing gear of shimmy Fader device |
| CN108394552A (en) * | 2018-03-06 | 2018-08-14 | 北京特种机械研究所 | A kind of piston type shimmy-damper based on atmospheric pressure compensating |
| CN109869429A (en) * | 2017-12-01 | 2019-06-11 | 中国飞机强度研究所 | A kind of novel friction type shimmy-damper |
-
2020
- 2020-03-31 CN CN202010244172.9A patent/CN113460293B/en active Active
Patent Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB503807A (en) * | 1937-11-30 | 1939-04-14 | Ribbesford Company Ltd | Improvements in or relating to landing gear for aircraft |
| US20090224100A1 (en) * | 2008-03-05 | 2009-09-10 | Goodrich Corporation | Shimmy damper for aircraft landing gear |
| CN103038538A (en) * | 2010-07-29 | 2013-04-10 | 梅西耶-道提股份有限公司 | Hydraulic shimmy damper for aircraft landing gear |
| CN201800917U (en) * | 2010-09-30 | 2011-04-20 | 湖南山河科技股份有限公司 | Anti-shimmy mechanism of landing wheel |
| CN202244082U (en) * | 2011-08-29 | 2012-05-30 | 湖南山河科技股份有限公司 | Shimmy damper for rotor wing of helicopter |
| CN103523218A (en) * | 2013-10-12 | 2014-01-22 | 中国航天空气动力技术研究院 | Unmanned plane damping-adjustable front-wheel shimmy-damper |
| CN107780744A (en) * | 2016-08-31 | 2018-03-09 | 赵芬 | Angle positioning and self-closing hinge can be adjusted |
| RU2648483C1 (en) * | 2016-09-19 | 2018-03-26 | Олег Савельевич Кочетов | Combined vibration isolator |
| CN107878738A (en) * | 2016-09-29 | 2018-04-06 | 赛峰起落架系统公司 | It is equipped with the aircraft landing gear of shimmy Fader device |
| CN109869429A (en) * | 2017-12-01 | 2019-06-11 | 中国飞机强度研究所 | A kind of novel friction type shimmy-damper |
| CN108394552A (en) * | 2018-03-06 | 2018-08-14 | 北京特种机械研究所 | A kind of piston type shimmy-damper based on atmospheric pressure compensating |
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| CN113460293B (en) | 2024-01-30 |
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Address after: 412002 no.768 Zhixing street, Lusong District, Zhuzhou City, Hunan Province Applicant after: Shanhe Xinghang Industrial Co.,Ltd. Address before: 412002 no.768 Zhixing street, Lusong District, Zhuzhou City, Hunan Province Applicant before: HUNAN SUNWARD SCIENCE & TECHNOLOGY Co.,Ltd. |
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