An external sound insulation device and sound insulation method for a siphon-type rainwater drainage pipe

By designing an external sound insulation device for siphon-type rainwater drainage pipes with strong adaptability, the limitation of existing devices on pipe shape has been solved, realizing convenient installation and efficient noise isolation for pipes of different shapes and lengths.

CN115506541BActive Publication Date: 2025-10-31ANHUI SHENGFENG CONSTR ENG CO LTD
View PDF 4 Cites 0 Cited by

Patent Information

Application Number
CN202211219757.0
Authority / Receiving Office
CN · China
Patent Type
Patents(China)
Current Assignee / Owner
Filing Date
2022-09-29
Publication Date
2025-10-31
Estimated Expiration
2042-09-29

AI Technical Summary

Technical Problem

The external sound insulation devices for existing siphonic rainwater drainage pipes have limitations on the pipe's shape during installation, making it difficult to conveniently handle the wrapping and noise blocking of curved and long sections.

Method used

An external sound insulation device was designed, comprising an upper device housing, a lower device housing, a sliding ring, a sealing plate, a support frame, a clamping ring, and a connecting ring. The sliding ring and clamping ring adapt to different pipe shapes, and the sealing plate and connecting ring enable convenient installation and fixation. Sound-absorbing cotton absorbs noise.

Benefits of technology

It enables flexible installation and efficient noise isolation of siphonic rainwater drainage pipes of different shapes and lengths, improving the adaptability and connection efficiency of the device.

✦ Generated by Eureka AI based on patent content.

Smart Images

  • Figure CN115506541B_ABST
    Figure CN115506541B_ABST
Patent Text Reader

Abstract

This invention discloses an external sound insulation device and method for a siphonic rainwater drainage pipe, comprising an upper device housing with a lower device housing at its lower end; a first sliding ring on one side of a second sliding ring, the interior of the first sliding ring being slidably connected to the exterior of the second sliding ring; and a first sealing plate disposed on one side between the upper and lower device housings, with clamping blocks at both ends of the outer side of the first sealing plate, one side of each clamping block being rotatably connected to the first sealing plate. The orientation of the lower device housing can be adjusted by sliding the second sliding ring within the first sliding ring to accommodate different bending angles. Furthermore, the first and second sealing plates respectively fill the space between the upper and lower device housings, thus adapting to the straight pipe. The device can be rotated and adjusted according to actual usage requirements.
Need to check novelty before this filing date? Find Prior Art

Description

Technical Field

[0001] This invention relates to the field of noise reduction technology for drainage pipes, specifically to an external sound insulation device and sound insulation method for a siphon-type rainwater drainage pipe. Background Technology

[0002] Siphon drainage is caused by the attraction between liquid molecules and potential energy. It utilizes the pressure difference of the water column to make water rise and then flow to a lower place. Water will flow from the side with greater net pressure to the side with less net pressure until the net pressure on both sides is equal, and the water level in the container becomes equal, at which point the water stops flowing. This drainage method is used for roof drainage. However, the drainage process requires the use of transmission pipes. The water flow inside the transmission pipes will produce water flow noise during the process. The continuous flow of water will continuously generate noise, affecting the working and living environment of the surrounding people. In order to avoid this situation, people have designed an external sound insulation device for water pipes.

[0003] For example, Chinese utility model patent CN111828738A discloses a multifunctional document comparison instrument, including a sound insulation and noise reduction device. The sound insulation and noise reduction device consists of a sound insulation and noise reduction plate and an installation frame. The sound insulation and noise reduction plate is set vertically and is embedded in the passage of the wall through the installation frame. The sound insulation and noise reduction plate consists of an upper plate, a middle plate, and a lower plate, which are stacked sequentially. A through hole a is opened between the upper plate and the middle plate to facilitate the passage of large pipes, and a through hole b is opened between the middle plate and the lower plate to facilitate the passage of small pipes. A rubber buffer sleeve is provided in the through hole a. Compared with the prior art, the present invention designs a through-wall pipe sound insulation and noise reduction device for the through-wall passage of hydropower plant buildings. It can effectively isolate the working area, prevent the noise of the turbine room from affecting other working areas, and is very convenient to install and disassemble without affecting the safe operation of the original pipeline.

[0004] However, the device disclosed in the aforementioned Chinese utility model patent needs to be installed inside the wall during actual use. The installation will limit the shape of the pipe and cannot easily cope with bends and long-distance wrapping and noise blocking. Therefore, it does not meet the existing needs. In this regard, we propose an external sound insulation device and sound insulation method for siphon rainwater drainage pipes. Summary of the Invention

[0005] The purpose of this invention is to provide an external sound insulation device and a sound insulation method for a siphon-type rainwater drainage pipe, so as to solve the problem that the external sound insulation device for drainage pipes mentioned in the background art is limited by the external shape of the pipe.

[0006] To achieve the above objectives, the present invention provides the following technical solution: an external sound insulation device and sound insulation method for a siphon-type rainwater drainage pipe, comprising an upper device housing, wherein a lower device housing is provided at the lower end of the upper device housing;

[0007] The second sliding ring is disposed at the upper end of one side of the lower device housing. One side of the second sliding ring is fixedly connected to the lower device housing. A first sliding ring is disposed on the outer side of the second sliding ring, and one end of the first sliding ring is fixedly connected to the lower end of one side of the upper device housing. The inside of the first sliding ring is slidably connected to the outside of the second sliding ring.

[0008] The first sealing plate is disposed on one side between the upper device housing and the lower device housing. Clamping blocks are provided at both ends of the outer side of the first sealing plate. One side of the two clamping blocks is rotatably connected to the first sealing plate. A rotating handle is provided at one end of the clamping block, and the rotating handle is fixedly connected to the clamping block.

[0009] Preferably, a second sealing plate is provided on the other side between the upper device housing and the lower device housing. A hanging frame is provided at one end of the second sealing plate, and one side of the hanging frame is fixedly connected to one side of the second sealing plate. A connecting frame is provided in the middle of one side of both the upper device housing and the lower device housing, and the connecting frame is connected to the hanging frame slot.

[0010] Preferably, a pair of support frames are provided on one side of the upper device housing and the lower device housing, and one side of each of the support frames is fixedly connected to one side of the upper device housing and the lower device housing. A sliding strip is provided on the outer side of the support frame, and the outer side of the sliding strip is slidably connected to the inner side of the support frame.

[0011] Preferably, each of the plurality of sliding bars is provided with a clamping ring on its outer side, and a third sliding ring is provided at one end of each of the plurality of clamping rings, and one end of the third sliding ring is fixedly connected to the clamping ring. A clamping spring is provided on one side of the outer side of the sliding bar, and the two ends of the clamping spring are fixedly connected to the sliding bar and the support frame, respectively.

[0012] Preferably, each of the two connecting frames is provided with a suspension frame at one end, and one side of the suspension frame is fixedly connected to the outer shell of the upper device. One end of the suspension frame is provided with a bearing frame, and one side of the bearing frame is provided with a first bearing rod. Several second bearing rods are evenly distributed laterally on the outside of the first bearing rods, and the second bearing rods, the first bearing rods and the bearing frame are all welded and fixed together.

[0013] Preferably, a connecting block is provided on one side of the lower end of the lower device housing, and a first connecting ring is provided at the lower end of the connecting block, and the first connecting ring, the connecting block and the lower device housing are all fixedly connected.

[0014] Preferably, the upper end of the outer shell of the upper device is provided with a second connecting ring, the lower end of the inner part of the second connecting ring is provided with a second annular sliding rail, the lower end of the second annular sliding rail is provided with a first annular sliding rail, and the first annular sliding rail is slidably connected to the first connecting ring.

[0015] Preferably, the upper device housing and the lower device housing are provided with a plurality of sound-absorbing cotton in an annular shape inside, and the sound-absorbing cotton is fixedly connected to one side of the interior of the upper device housing.

[0016] Preferably, both ends of the first sealing plate are provided with clamping grooves, and the clamping grooves are respectively connected to the upper device housing, the lower device housing and the side slot of the suspension frame.

[0017] The sound insulation method for the external sound insulation device of the siphon rainwater drainage pipe includes the following steps:

[0018] Step 1: Insert the pipe into the lower housing and out of the upper housing. During insertion, the compression of the pipe's shape will push the clamping ring through the third sliding ring. After being pushed, the two clamping rings move to opposite ends and are squeezed by the elasticity of the clamping springs, thus squeezing and completing the clamping.

[0019] Step 2: For housings with different shapes, the upper housing slides on the second sliding ring outside the lower housing via the first sliding ring;

[0020] Step 3: Slide and adjust the angle between the upper device housing and the lower device housing. During the angle adjustment process, the first sealing plate fills one side between the upper device housing and the lower device housing. By rotating the handle, the clamping block is driven to rotate. According to the fixed position, the clamping block and the clamping groove can fix the upper device housing and the suspension frame respectively.

[0021] Step 4: The second sealing plate is fixed by connecting the two ends of the suspension frame to the connecting bracket slots on one side of the upper device housing and the lower device housing, and can fix the other side between the upper device housing and the suspension frame.

[0022] Step 5: When connecting through multiple devices, the first connecting ring at the lower end of the outer shell of one device is slidably placed on the first annular sliding rail at the upper end of the outer shell of another device. After being slid into the device, it rotates around the pipe as the center. The rotation is then restricted by the second annular sliding rail, thus completing the fixation.

[0023] Compared with the prior art, the beneficial effects of the present invention are:

[0024] 1. The present invention provides a lower device housing at the lower end of the upper device housing, a second sliding ring at the upper end of one side of the lower device housing, and a first sliding ring at the outer side of the second sliding ring. In actual use, the orientation of the lower device housing can be adjusted by sliding the second sliding ring through the inside of the first sliding ring to adapt to different bending angles. On the other hand, the first sealing plate and the second sealing plate respectively fill the two sides between the upper device housing and the lower device housing, thereby adapting to the straight pipe. The device can rotate and adjust according to actual use requirements to meet actual use needs.

[0025] 2. The present invention provides support frames at both ends of the inner side of the upper and lower device housings. A sliding strip is provided on the outer side of the support frame, and a clamping ring is provided at one end of the sliding strip. A third sliding ring is provided at the outer end of the clamping ring. In actual use, the pipe to be wrapped is inserted through the lower end of the lower device housing and extends out from the upper end of the upper device housing. During the insertion process, the clamping ring can be pushed to both ends by the third sliding ring, and the elasticity of the clamping spring can push and restrict it, thereby fixing it to the outside of the pipe.

[0026] 3. The present invention provides a second connecting ring at the upper end of the outer shell of the upper device, a second annular sliding rail at the lower end of the inner part of the second connecting ring, and a first annular sliding rail at the lower end of the second annular sliding rail. In actual use, since the lengths of the connecting pipes are different, they are supported by connecting blocks, and the first connecting ring is slidably placed inside the first annular sliding rail and rotates. The rotation is restricted by the second annular sliding rail to complete the connection of multiple devices. The connection method is convenient and efficient, and can meet the actual use needs. Attached Figure Description

[0027] Figure 1 This is a front view of the internal structure of the device of the present invention;

[0028] Figure 2 For the present invention Figure 1 Enlarged view of a portion of region A in the middle;

[0029] Figure 3 This is a front view of the folded internal structure of the device of the present invention;

[0030] Figure 4 This is a front view of the transmission structure inside the support frame of the present invention;

[0031] Figure 5 This is a cross-sectional view showing the positional relationship between the second sliding ring and the clamping ring of the present invention;

[0032] Figure 6 This is an exploded view showing the positional relationship between the second connecting ring and the first connecting ring of the present invention.

[0033] In the diagram: 1. Upper device housing; 2. Lower device housing; 3. Suspension frame; 4. First sliding ring; 5. Second sliding ring; 6. First sealing plate; 7. Clamping block; 8. Clamping groove; 9. Rotating handle; 10. Second sealing plate; 11. Suspension frame; 12. Connecting frame; 13. Sound-absorbing cotton; 14. Support frame; 15. Sliding strip; 16. Clamping ring; 17. Connecting block; 18. First connecting ring; 19. Second connecting ring; 20. First annular sliding rail; 21. Second annular sliding rail; 22. Bearing frame; 23. First bearing rod; 24. Second bearing rod; 25. Second sliding ring; 26. Clamping spring. Detailed Implementation

[0034] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0035] Please see Figure 1-6 An embodiment of the present invention provides: an external sound insulation device and sound insulation method for a siphon rainwater drainage pipe, comprising an upper device housing 1, and a lower device housing 2 provided at the lower end of the upper device housing 1;

[0036] The second sliding ring 5 is disposed on the upper end of one side of the lower device housing 2. One side of the second sliding ring 5 is fixedly connected to the lower device housing 2. A first sliding ring 4 is disposed on the outer side of the second sliding ring 5, and one end of the first sliding ring 4 is fixedly connected to the lower end of one side of the upper device housing 1. The inside of the first sliding ring 4 is slidably connected to the outside of the second sliding ring 5.

[0037] The first sealing plate 6 is disposed on one side between the upper device housing 1 and the lower device housing 2. Both ends of the outer side of the first sealing plate 6 are provided with clamping blocks 7. One side of the two clamping blocks 7 is rotatably connected to the first sealing plate 6. One end of the clamping block 7 is provided with a rotating handle 9, and the rotating handle 9 is fixedly connected to the clamping block 7.

[0038] Please see Figure 1 and Figure 3 A second sealing plate 10 is provided on the other side between the upper device housing 1 and the lower device housing 2. A hanging frame 11 is provided at one end of the second sealing plate 10, and one side of the hanging frame 11 is fixedly connected to one side of the second sealing plate 10. A connecting frame 12 is provided in the middle of one side of the upper device housing 1 and the lower device housing 2, and the connecting frame 12 is connected to the hanging frame 11 in a slot. The other side between the upper device housing 1 and the lower device housing 2 can be fixedly connected through the second sealing plate 10.

[0039] Please see Figure 1 , Figure 2 , Figure 3 , Figure 4and Figure 5 A pair of support frames 14 are provided on one side inside the upper device housing 1 and the lower device housing 2. One side of each of the support frames 14 is fixedly connected to one side inside the upper device housing 1 and the lower device housing 2. A sliding strip 15 is provided on one side outside the support frame 14, and the outside of the sliding strip 15 is slidably connected to the inside of the support frame 14. By sliding, it can accommodate transmission pipes of different diameters.

[0040] Please see Figure 1 , Figure 2 , Figure 3 , Figure 4 and Figure 5 Each of the sliding bars 15 is provided with a clamping ring 16 on its outside. One end of each clamping ring 16 is provided with a third sliding ring 25, and one end of the third sliding ring 25 is fixedly connected to the clamping ring 16. A clamping spring 26 is provided on one side of the outside of the sliding bar 15. The two ends of the clamping spring 26 are fixedly connected to the sliding bar 15 and the support frame 14 respectively. The device can be fixed by clamping, so that the device is fixed to the outside of the pipe.

[0041] Please see Figure 1 , Figure 2 and Figure 3 Each of the two connecting frames 12 has a suspension frame 3 at one end, and one side of the suspension frame 3 is fixedly connected to the outer shell 1 of the upper device. One end of the suspension frame 3 is provided with a bearing frame 22. One side of the inner side of the bearing frame 22 is provided with a first bearing rod 23. Several second bearing rods 24 are evenly distributed laterally on the outside of the first bearing rods 23. The second bearing rods 24, the first bearing rods 23 and the bearing frame 22 are all welded and fixed together. The outer part of the device can be wrapped and protected by the bearing frame 22, the first bearing rods 23 and the second bearing rods 24.

[0042] Please see Figure 1 , Figure 2 , Figure 3 and Figure 6 A connecting block 17 is provided on one side of the lower end of the lower device housing 2. A first connecting ring 18 is provided at the lower end of the connecting block 17. The first connecting ring 18, the connecting block 17 and the lower device housing 2 are all fixedly connected. The second annular sliding rail 21 can be restricted by the connecting block 17 sliding inside the first annular sliding rail 20.

[0043] Please see Figure 1 , Figure 2 , Figure 3 and Figure 6The upper end of the outer shell 1 of the upper device is provided with a second connecting ring 19. The lower end of the inner part of the second connecting ring 19 is provided with a second annular sliding rail 21. The lower end of the second annular sliding rail 21 is provided with a first annular sliding rail 20. The first annular sliding rail 20 is slidably connected to the first connecting ring 18. The first connecting ring 18 can be accommodated and stored through the first annular sliding rail 20, and the connection of several devices can be completed.

[0044] Please see Figure 1 , Figure 2 and Figure 3 The upper device housing 1 and the lower device housing 2 are provided with a number of sound-absorbing cotton 13 arranged in a ring inside, and the sound-absorbing cotton 13 is fixedly connected to one side of the interior of the upper device housing 1. The sound-absorbing cotton 13 can absorb noise and block noise.

[0045] Please see Figure 1 and Figure 3 Both ends of the first sealing plate 6 are provided with clamping grooves 8, and the clamping grooves 8 are respectively connected to the slots on one side of the upper device housing 1, the lower device housing 2 and the suspension frame 3. The sealing performance of the device can be improved by restricting the clamping grooves 8.

[0046] The sound insulation method for the external sound insulation device of the siphon rainwater drainage pipe includes the following steps:

[0047] Step 1: Insert the pipe into one end of the lower device housing 2 and out one end of the upper device housing 1. During the insertion process, the compression of the pipe shape will push the clamping ring 16 through the third sliding ring 25. After being pushed, the two clamping rings 16 move to both ends respectively, and are squeezed by the elasticity of the clamping spring 26, thus squeezing and completing the clamping.

[0048] Step 2: To handle different shaped housings, the upper housing 1 slides on the second sliding ring 5 outside the lower housing 2 via the first sliding ring 4.

[0049] Step 3: Slide and adjust the angle between the upper device housing 1 and the lower device housing 2. During the angle adjustment process, the first sealing plate 6 fills one side between the upper device housing 1 and the lower device housing 2. By rotating the handle 9, the clamping block 7 is driven to rotate. According to the fixed position, the clamping block 7 and the clamping groove 8 can fix the upper device housing 1 and the suspension frame 3 respectively.

[0050] Step 4: The second sealing plate 10 is fixed by connecting the two ends of the suspension frame 11 to the connecting bracket 12 on one side of the upper device housing 1 and the lower device housing 2 through the slots. This fixes the other side between the upper device housing 1 and the suspension bracket 3.

[0051] Step 5: When connecting through multiple devices, the first connecting ring 18 at the lower end of the outer shell 2 of one device is slidably placed on the first annular sliding rail 20 at the upper end of the outer shell 1 of another device. After being slid into the device, it rotates around the pipe as the center. The rotation is restricted by the second annular sliding rail 21, thus completing the fixation.

[0052] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. An external sound insulation device for a siphon-type rainwater drainage pipe, comprising an upper device housing (1), wherein a lower device housing (2) is provided at the lower end of the upper device housing (1), characterized in that: The second sliding ring (5) is disposed on the upper end of one side of the lower device housing (2). One side of the second sliding ring (5) is fixedly connected to the lower device housing (2). A first sliding ring (4) is disposed on the outer side of the second sliding ring (5), and one end of the first sliding ring (4) is fixedly connected to the lower end of one side of the upper device housing (1). The inside of the first sliding ring (4) is slidably connected to the outside of the second sliding ring (5). The first sealing plate (6) is disposed on one side between the upper device housing (1) and the lower device housing (2). Both ends of the outer side of the first sealing plate (6) are provided with clamping blocks (7). One side of the two clamping blocks (7) is rotatably connected to the first sealing plate (6). One end of the clamping block (7) is provided with a rotating handle (9), and the rotating handle (9) is fixedly connected to the clamping block (7). A second sealing plate (10) is provided on the other side between the upper device housing (1) and the lower device housing (2). A hanging frame (11) is provided at one end of the second sealing plate (10), and one side of the hanging frame (11) is fixedly connected to one side of the second sealing plate (10). A connecting frame (12) is provided in the middle of one side of both the upper device housing (1) and the lower device housing (2), and the connecting frame (12) is connected to the hanging frame (11) in a slot. A pair of support frames (14) are provided on one side inside the upper device housing (1) and the lower device housing (2). One side of each of the support frames (14) is fixedly connected to one side inside the upper device housing (1) and the lower device housing (2). A sliding strip (15) is provided on one side outside the support frame (14), and the outside of the sliding strip (15) is slidably connected to the inside of the support frame (14). A clamping ring (16) is provided on the outside of each of the sliding strips (15). A third sliding ring (25) is provided at one end of the clamping ring (16), and one end of the third sliding ring (25) is fixedly connected to the clamping ring (16). A clamping spring (26) is provided on one side of the outer side of the sliding bar (15). The two ends of the clamping spring (26) are fixedly connected to the sliding bar (15) and the support frame (14) respectively. A connecting block (17) is provided on one side of the lower end of the lower device housing (2). A first connecting ring (18) is provided at the lower end of the connecting block (17), and the first connecting ring (18), the connecting block (17) and the lower device housing (2) are all fixedly connected. A second connecting ring (19) is provided at the upper end of the upper device housing (1). A second annular sliding rail (21) is provided at the lower end of the inner side of the second connecting ring (19). A first annular sliding rail (20) is provided at the lower end of the second annular sliding rail (21), and the first annular sliding rail (20) is slidably connected to the first connecting ring (18).

2. The external sound insulation device for a siphon-type rainwater drainage pipe according to claim 1, characterized in that: One end of each of the two connecting frames (12) is provided with a suspension frame (3), and one side of the suspension frame (3) is fixedly connected to the outer shell (1) of the upper device. One end of the suspension frame (3) is provided with a bearing frame (22), and one side of the bearing frame (22) is provided with a first bearing rod (23). Several second bearing rods (24) are evenly distributed laterally on the outside of the first bearing rod (23), and the second bearing rods (24), the first bearing rods (23) and the bearing frame (22) are all welded and fixed together.

3. The external sound insulation device for a siphon-type rainwater drainage pipe according to claim 2, characterized in that: The upper device housing (1) and the lower device housing (2) are provided with a number of sound-absorbing cotton (13) arranged in a ring shape inside, and the sound-absorbing cotton (13) is fixedly connected to one side of the interior of the upper device housing (1).

4. The external sound insulation device for a siphon-type rainwater drainage pipe according to claim 3, characterized in that: The first sealing plate (6) has clamping grooves (8) at both ends inside, and the clamping grooves (8) are respectively connected to the slots on one side of the upper device housing (1), the lower device housing (2) and the suspension frame (3).

5. A sound insulation method based on the external sound insulation device of the siphon-type rainwater drainage pipe according to claim 4, characterized in that: Includes the following steps: Step 1: Insert the pipe into one end of the lower device housing (2) and out one end of the upper device housing (1). During the insertion process, the compression of the pipe shape will push the clamping ring (16) through the third sliding ring (25). After being pushed, the two clamping rings (16) move to both ends respectively, and are squeezed by the elasticity of the clamping spring (26) to squeeze and complete the clamping. Step 2: To deal with different shaped shells, the upper device shell (1) slides on the second sliding ring (5) outside the lower device shell (2) via the first sliding ring (4); Step 3: Slide and adjust the angle between the upper device housing (1) and the lower device housing (2). During the angle adjustment process, the first sealing plate (6) fills one side between the upper device housing (1) and the lower device housing (2). By rotating the handle (9), the clamping block (7) is driven to rotate. According to the fixed position, the clamping block (7) and the clamping groove (8) can fix the upper device housing (1) and the suspension frame (3) respectively. Step 4: The second sealing plate (10) is fixed by connecting the two ends of the suspension frame (11) to the connecting bracket (12) on one side of the upper device housing (1) and the lower device housing (2), and can fix the other side between the upper device housing (1) and the suspension bracket (3). Step 5: When connecting through multiple devices, the first connecting ring (18) at the lower end of the outer shell (2) of one device is slidably placed inside the outer shell (1) of another device. After being slid into the device, it rotates around the pipe as the center. The rotation is restricted by the second ring sliding rail (21), and the restriction is completed.

Citation Information

Patent Citations

  • Sound insulation and noise reduction device for wall-penetrating pipeline in hydropower plant

    CN111828738A

  • Bayonet connection for connecting connector to tubular body, bayonet ring, and tubular body

    CN109642692A

  • Adjustable elbow joint

    CN211145721U

  • Angle-adjustable elbow joint

    CN217302085U