Counterweight structure of skid undercarriage and skid undercarriage

Abstract

The utility model relates to a skid undercarriage counterweight structure and a skid undercarriage, belongs to the technical field of aerospace, and solves the problem that the undercarriage resonates in ground experiments and test flight processes due to actual skid undercarriage products and design deviations. The device comprises a central shaft and a balancing weight, the number of the balancing weights is multiple, and the balancing weights are arranged on the center shaft in a sleeving mode. And the counterweight structure is arranged in the undercarriage second pipe. According to the skid undercarriage, the structure of the undercarriage is not changed, the counterweight structure is arranged in the first pipe of the skid undercarriage, and the resonance phenomenon of the undercarriage is weakened or avoided.

Description

Technical Field

[0001] This utility model relates to the field of aerospace technology, and in particular to a skid landing gear counterweight structure and a skid landing gear. Background Technology

[0002] Skid landing gear is commonly used on small and medium-sized helicopters. During the manufacturing process, assembly techniques, engine and rotor characteristics, and flight test environments, the actual product may deviate from the design weight or specifications, causing landing gear resonance. Utility Model Content

[0003] Based on the above analysis, the present invention aims to provide a skid landing gear counterweight structure and skid landing gear to solve the problem of landing gear resonance during ground testing and flight testing.

[0004] The objective of this utility model is mainly achieved through the following technical solutions:

[0005] One aspect of this utility model is to provide a skid landing gear counterweight structure, including a central shaft and a counterweight block;

[0006] The counterweight has multiple components, and the counterweight is sleeved on the central shaft;

[0007] The central shaft is fixed inside the skid landing gear.

[0008] Furthermore, the central shaft has a screw portion, and the counterweight has an internal thread; the counterweight is threadedly connected to the screw portion.

[0009] Furthermore, it also includes a fastener; the fastener has mounting holes inside;

[0010] The central shaft has a mounting portion that can be inserted into the mounting hole.

[0011] Furthermore, it also includes a spring; in its natural state, the length of the spring is the same as the length of the screw portion;

[0012] A limiting part is provided at the end of the central shaft near the mounting part; the spring is disposed between the counterweight and the limiting part.

[0013] Furthermore, it also includes a sleeve; the sleeve is fitted over the outside of the counterweight;

[0014] The sleeve wall is provided with an elongated groove, the length of which is in the same direction as the axis of the sleeve.

[0015] A second aspect of this utility model provides a skid landing gear, including a first tube, a second tube, and a skid landing gear counterweight structure.

[0016] The first tube is disposed on the second tube; and the first tube is connected to the second tube;

[0017] The second tube is arranged in parallel;

[0018] The counterweight structure is disposed inside the second tube, and the central axis is coaxial with the second tube.

[0019] Furthermore, the second pipe includes a first section and a second section; the second section is disposed at both ends of the first section;

[0020] The second segment has a main segment and a tail segment. The outer diameter of the tail segment is the same as the inner diameter of the first segment, and the tail segment can be inserted into the first segment.

[0021] Furthermore, it also includes limit bolts;

[0022] The tail section has a threaded hole, and the first section has a through hole at the position corresponding to the threaded hole; the limiting bolt is disposed in the threaded hole and the through hole, and the limiting bolt is used to connect the first section and the second section;

[0023] The limiting bolt abuts against the end of the central shaft to limit the end of the counterweight structure near the second section.

[0024] Furthermore, the first section is provided with a limiting groove for fixing the counterweight structure to the first section.

[0025] Furthermore, multiple counterweight structures are provided, and the multiple counterweight structures are provided at different positions inside the second tube.

[0026] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0027] (1) Compared with the prior art, the counterweight structure of this utility model sets multiple counterweight blocks on the central axis and adds or subtracts counterweight blocks according to the required counterweight, which is simple and convenient.

[0028] (2) The spring of this utility model is sleeved on the central shaft. In its natural state, the length of the spring is the same as the thread length of the central shaft. The spring is used to provide sufficient preload to the counterweight structure when the counterweight mass is small and the counterweight block cannot cover the entire screw, so as to prevent the counterweight block from oscillating in the skid landing gear and affecting the use of the landing gear.

[0029] (3) The sleeve of this utility model has a long groove in the middle and a C-shaped cross section. It is sleeved on the outside of the counterweight to compensate for and absorb the noise and friction caused by vibration between the counterweight and the inner wall of the skid tube.

[0030] (4) The counterweight structure of this utility model is set inside the second tube and is coaxial with the second tube. The limiting groove is used to fix the stop block inside the second tube and limit one end of the counterweight structure; the limiting bolt is used to fix the second section to the first section on the one hand, and abuts against the end of the central axis away from the stop block on the other hand, and is used to limit the other end of the counterweight structure.

[0031] (5) Compared with the prior art, this utility model does not change the landing gear structure. According to the landing gear mass distribution, a counterweight structure is installed at different positions inside the second tube of the skid landing gear. The counterweight structure is coaxially set with the second tube. By changing the overall mass of the landing gear and the balance mass distribution, the landing gear mode is adjusted, thereby reducing or avoiding the phenomenon of resonance of the landing gear.

[0032] In this invention, the above-described technical solutions can be combined with each other to achieve more preferred combinations. Other features and advantages of this invention will be set forth in the following description, and some advantages will become apparent from the description or be learned by practicing this invention. The objectives and other advantages of this invention can be realized and obtained from the details specifically pointed out in the text and accompanying drawings. Attached Figure Description

[0033] The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of the invention. Throughout the drawings, the same reference numerals denote the same parts.

[0034] Figure 1 This is a schematic diagram of the skid landing gear structure;

[0035] Figure 2 This is a schematic diagram of the counterweight structure;

[0036] Figure 3 A schematic diagram of the structure with the central axis;

[0037] Figure 4 This is a schematic diagram of the second tube of the skid landing gear.

[0038] Figure label:

[0039] 1-Counterweight structure, 11-Central shaft, 111-Screw section, 112-Limiting section, 113-Mounting section, 12-Counterweight block, 13-Fixing component, 14-Spring, 15-Sleeve, 151-Long groove, 16-Nut, 2-First tube, 3-Second tube, 31-First section, 311-Limiting groove, 312-Through hole, 32-Second section, 321-Main section, 322-Tail section, 3221-Threaded hole, 4-Limiting bolt. Detailed Implementation

[0040] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which constitute a part of the present invention and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not intended to limit the scope of the present invention.

[0041] Example 1

[0042] A specific embodiment of this utility model is as follows: Figure 1 and Figure 2 As shown, a skid landing gear counterweight structure 1 is disclosed, including a central shaft 11 and a counterweight block 12.

[0043] Multiple counterweights 12 are provided, and the multiple counterweights 12 are sleeved on the central shaft 11. For example, the middle part of the central shaft 11 is a screw part 111 with external thread, and the counterweights 12 have internal threads; the counterweights 12 can be threadedly connected to the central shaft 11 for fixation.

[0044] like Figure 3 As shown, the end of the central shaft 11 is provided with a mounting portion 113 and a limiting portion 112. Exemplarily, the diameter of the limiting portion 112 is larger than the diameter of the screw portion 111 of the central shaft 11, and it is a circumferential flange provided on one side of the screw. The mounting portion 113 is provided on the side of the limiting portion 112 opposite to the screw portion 111. The mounting portion 113 is in the shape of a round rod, and its diameter is smaller than the screw diameter.

[0045] Furthermore, it also includes a fastener 13. The fastener 13 is a boss structure, including a large-diameter portion and a small-diameter portion. The large-diameter portion is used to fix it to the skid landing gear, and the small-diameter portion is used to fix the end of the central shaft 11. The small-diameter portion has a mounting hole inside, and the mounting portion 113 of the central shaft 11 can be inserted into the mounting hole to fix the central shaft 11. In one embodiment, the fastener 13 is fixed to the skid tube by welding or other means. The fastener 13 can also be a cylinder of equal diameter with a central hole for inserting the mounting portion 113.

[0046] Furthermore, it also includes a spring 14. The spring 14 is disposed between the counterweight 12 and the limiting part 112. In its natural state, the length of the spring 14 is the same as the thread length of the central shaft 11. The spring 14 is used to provide sufficient preload to the counterweight structure 1 when the counterweight 12 is too small to cover the entire screw, so as to prevent the counterweight 12 from oscillating in the skid landing gear and affecting the use of the landing gear.

[0047] Furthermore, it also includes a sleeve 15. The sleeve 15 is fitted onto the outside of the counterweight 12. The length of the sleeve 15 is the same as the length of the entire screw.

[0048] The sleeve 15 has a long groove 151 on its wall surface, and the length direction of the long groove 151 is the same as the axial direction of the sleeve 15.

[0049] The sleeve 15 is made of non-metallic material. For example, the sleeve 15 is made of nylon, PC, ABS, etc., and is used to compensate for and absorb the noise and friction caused by vibration between the counterweight 12 and the inner wall of the skid tube.

[0050] For example, a nut 16 is also provided on the side of the counterweight 12 away from the fixing member 13 for fixing the counterweight 12.

[0051] Compared with the prior art, the counterweight structure 1 of this embodiment sets multiple counterweight blocks 12 on the central axis 11, and adds or subtracts counterweight blocks 12 according to the required counterweight, which is simple and convenient.

[0052] Example 2

[0053] This embodiment discloses a skid landing gear, including a first tube 2, a second tube 3, and the skid landing gear counterweight structure 1 described in Embodiment 1.

[0054] The first pipe 2 is installed on the second pipe 3, and the first pipe 2 is connected to the second pipe 3.

[0055] For example, the first tube 2 is an arc-shaped tube.

[0056] The second tube is set in parallel with the third tube.

[0057] The counterweight structure 1 is located inside the second tube 3, and the central axis 11 of the counterweight structure 1 is coaxial with the second tube 3.

[0058] like Figure 4 As shown, preferably, the second pipe 3 includes a first section 31 and a second section 32. The first section 31 is located at the center, and the second section 32 is located at both ends of the first section 31.

[0059] The first section 31 is a straight pipe, and a limiting groove 311 is provided at the near end of the first section 31 corresponding to the end position of the counterweight structure 1, for fixing the fastener 13 of the counterweight structure 1 to the first section 31. For example, the fixing method can be welding or threaded connection.

[0060] The second section 32 has an arc-shaped structure, consisting of a main section 321 and a tail section 322. The outer diameter of the main section 321 is the same as that of the first section 31. The tail section 322 is a straight tube, and its outer diameter is the same as that of the first section 31. The tail section 322 can be inserted into the first section 31.

[0061] Furthermore, it also includes a limiting bolt 4. The tail section 322 has a threaded hole 3221, and the first section 31 has a through hole 312 corresponding to the position of the threaded hole 3221; the limiting bolt 4 is disposed in the threaded hole 3221 and the through hole 312 for fixing the first section 31. Furthermore, the end of the central shaft 11 away from the fixing member 13 abuts against the limiting bolt 4.

[0062] In this embodiment, the counterweight structure 1 is disposed inside the second tube 3 and is coaxially arranged with the second tube 3. The limiting groove 311 is used to fix the stop block inside the second tube 3 and limit one end of the counterweight structure 1; the limiting bolt 4 is used to fix the second section 32 to the first section 31 on the one hand, and abuts against the end of the central shaft 11 away from the fixing member 13 on the other hand, and is used to limit the other end of the counterweight structure 1.

[0063] Furthermore, multiple counterweight structures 1 can be provided in this embodiment, and they can be set at different positions of the second tube 3 of the skid landing gear according to the mass distribution of the skid landing gear, so as to change the overall mass of the landing gear, balance the mass distribution of the landing gear, and adjust the landing gear mode.

[0064] The usage method of this embodiment is as follows:

[0065] After the skid landing gear body is completed, the counterweight structure 1 is installed.

[0066] Step 1: Fix the fastener 13 to the central shaft 11; place one end of the fastener 13 at the opening of the first section 31 of the second tube 3, and push the fastener 13 and the central shaft 11 along the length of the first section 31 to the limiting groove 311, and weld the fastener 13 to the inside of the first section 31 at the limiting groove 311.

[0067] Step 2: Push the sleeve 15 from the opening of the first section 31 to the limiting part 112. Because the sleeve 15 has a long groove 151 on its wall and the material is elastic, it can adapt to the interior of the first section 31 and will fit tightly against the inner wall of the first section 31. The length of the sleeve 15 is the same as the length of the entire screw.

[0068] Step 3: Fit the spring 14 onto the central shaft 11. According to the weight of the counterweight, fit the counterweight 12 onto the central shaft 11, and fix the counterweight 12 to the central shaft 11 with threads.

[0069] Step 4: Insert the tail section of the second section 32 into the first section 31, insert the limiting bolt 4 into the threaded hole 3221 and the through hole 312 to fix the second section 32 to the first section 31, and limit the end of the counterweight structure 1.

[0070] Compared with the prior art, this embodiment does not change the landing gear structure. According to the mass distribution of the landing gear, a counterweight structure 1 is installed at different positions inside the second tube 3 of the skid landing gear. The counterweight structure 1 is coaxially arranged with the second tube 3. By changing the overall mass of the landing gear and balancing the mass distribution, the landing gear mode is adjusted, thereby reducing or avoiding the phenomenon of resonance of the landing gear.

[0071] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present utility model should be included within the protection scope of the present utility model.

Claims

1. A skid landing gear counterweight structure, characterized in that, Includes a central shaft (11) and a counterweight (12); The counterweight (12) has multiple components, and the counterweight (12) is sleeved on the central shaft (11); The central shaft (11) is fixed inside the skid landing gear.

2. The skid landing gear counterweight structure according to claim 1, characterized in that, The central shaft (11) has a screw section (111), and the counterweight (12) has an internal thread; the counterweight (12) is threadedly connected to the screw section (111).

3. The skid landing gear counterweight structure according to claim 2, characterized in that, It also includes a fastener (13); the fastener (13) has mounting holes inside; The central shaft (11) has a mounting portion (113) which can be inserted into the mounting hole.

4. The skid landing gear counterweight structure according to claim 3, characterized in that, It also includes a spring (14); in its natural state, the length of the spring (14) is the same as the length of the screw portion (111); A limiting part (112) is provided at the end of the central shaft (11) near the mounting part (113); the spring (14) is provided between the counterweight (12) and the limiting part (112).

5. The skid landing gear counterweight structure according to claim 1, characterized in that, It also includes a sleeve (15); the sleeve (15) is fitted over the outside of the counterweight (12); The sleeve (15) has a long groove (151) on its wall surface, and the length direction of the long groove (151) is the same as the axial direction of the sleeve (15).

6. A skid landing gear, characterized in that, Includes the first tube (2), the second tube (3), and the skid landing gear counterweight structure as described in any one of claims 1-5; The first tube (2) is disposed on the second tube (3); and the first tube (2) is connected to the second tube (3); The second tube (3) is arranged in parallel; The counterweight structure (1) is disposed inside the second tube (3), and the central shaft (11) is coaxial with the second tube (3).

7. The skid landing gear according to claim 6, characterized in that, The second pipe (3) includes a first section (31) and a second section (32); the second section (32) is disposed at both ends of the first section (31); The second section (32) has a main section (321) and a tail section (322), the outer diameter of which is the same as the inner diameter of the first section (31), and the tail section (322) can be inserted into the first section (31).

8. The skid landing gear according to claim 7, characterized in that, It also includes the limiting bolt (4); The tail section (322) has a threaded hole (3221), and the first section (31) has a through hole (312) at the position corresponding to the threaded hole (3221); the limiting bolt (4) is disposed in the threaded hole (3221) and the through hole (312), and the limiting bolt (4) is used to connect the first section (31) and the second section (32). The limiting bolt (4) abuts against the end of the central shaft (11) to limit the end of the counterweight structure (1) near the second section (32).

9. The skid landing gear according to claim 8, characterized in that, The first section (31) is provided with a limiting groove (311), which is used to fix the counterweight structure (1) to the first section (31).

10. The skid landing gear according to claim 6, characterized in that, Multiple counterweight structures (1) are provided, and the multiple counterweight structures (1) are provided at different positions inside the second tube (3).

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