A prefabricated adjustable height inspection well ring structure

Abstract

The application discloses a prefabricated adjustable-elevation inspection well ring structure, and an annular support groove is arranged at an upper end opening of a well shaft, a bottom of the well ring is detachably installed in the annular support groove, a plurality of first pushing mechanisms are uniformly and fixedly installed in an inner side wall of the well shaft in an annular array, a plurality of first pushing plates are uniformly and fixedly installed at the bottom of the well ring, the first pushing mechanism is used for adjusting the height of the corresponding first pushing plate, and a second pushing mechanism is used for adjusting the insertion depth of a second pushing plate. The application adjusts the distance between the well shaft and the bottom support plate through the second pushing mechanism, realizes coarse adjustment in the initial installation stage, sets the plurality of first pushing mechanisms between the well shaft and the well ring, adjusts the relative height of the well ring and the well shaft through the first pushing mechanism, realizes fine adjustment in the later installation stage, and the two-stage adjustment is independent of each other and is suitable for different site elevation deviations.

Description

Technical Field

[0001] This invention relates to the field of yy technology, specifically a prefabricated, assembled, adjustable elevation manhole ring structure. Background Technology

[0002] Precast assembly manholes are widely used auxiliary structures in underground pipeline projects such as municipal drainage, power, and communications. They have advantages such as stable quality, fast construction speed, and environmental protection and energy saving. The manhole ring is a component installed on the top of the manhole to support the manhole cover, and its top surface elevation must be precisely matched with the road surface design elevation.

[0003] However, in actual construction and use, the following problems exist in the elevation control of the manhole ring: First, initial elevation adjustment is difficult. Traditional manhole rings are typically installed directly on top of the manhole casing using grout, with the installation height adjusted based on the thickness of the bottom cement mortar layer. Because the mortar layer thickness is difficult to control precisely, it often requires repeated lifting of the manhole ring, adding or removing mortar, and repositioning. Each adjustment necessitates the use of hoisting equipment, making the process cumbersome, inefficient, and the adjustment accuracy usually only 5-10mm, which is insufficient to meet the flatness requirements of high-grade roads (specifications require ±3mm).

[0004] Secondly, manhole covers are prone to settlement during use. When the backfill soil around the manhole is not sufficiently compacted or the foundation is softened by groundwater, uneven settlement will occur between the manhole casing and the manhole cover, causing the top surface of the manhole cover to be lower than the road surface, forming a depression. A depressed manhole cover not only affects driving comfort but also generates impact noise, and in severe cases, can even cause the manhole cover to crack or the vehicle to bounce. Traditional manhole cover structures cannot compensate for the elevation changes after settlement and must be demolished and rebuilt, resulting in resource waste and traffic disruption.

[0005] Third, there is a lack of independent vertical adjustment mechanisms. Although some existing adjustable manhole covers have adjustment bolts, the adjustment mechanism is usually integrated with the manhole cover. When adjusting, the entire manhole cover needs to be lifted, which is inconvenient. Moreover, the adjustment screw directly bears the vehicle load transmitted by the manhole cover. Long-term use can easily lead to thread wear or deformation, affecting the adjustment accuracy and locking reliability.

[0006] Fourth, the height of the manhole cannot be finely adjusted on-site. The length of the prefabricated manhole is fixed. If there is a deviation in the foundation elevation during on-site installation, the top elevation of the manhole often cannot precisely match the road surface design elevation, requiring additional processing or the application of multiple layers of mortar, which increases the difficulty of construction.

[0007] Therefore, the present invention provides a prefabricated, adjustable elevation manhole ring structure to solve the above problems. Summary of the Invention

[0008] (a) Technical problems to be solved This invention provides a prefabricated, adjustable elevation manhole ring structure, aiming to solve the problems mentioned in the background art.

[0009] To achieve the above objectives, the present invention provides the following technical solution: A prefabricated, adjustable elevation manhole ring structure includes, from top to bottom, a manhole ring, a manhole cylinder, and a bottom support plate. A manhole cover is movably hinged to one end of the manhole ring. It also includes multiple first jacking mechanisms, first jacking plates, second jacking mechanisms, and second jacking plates. The wellbore has an annular support groove at the upper end, and the bottom of the well ring is detachably installed in the annular support groove. Multiple first jacking mechanisms are uniformly fixedly installed in a ring array on the inner sidewall of the wellbore, and the first jacking mechanism is located below the ring support groove; Multiple first push plates are evenly and fixedly installed at the bottom of the well ring, and the first push mechanism is used to adjust the height of the first push plate at the corresponding position. The bottom support plate is located at the bottom of the well ring, and a limit ring is fixedly installed on the upper part of the bottom support plate. The outer diameter of the limit ring matches the inner diameter of the well ring. A sealing groove is provided at the upper edge of the limit ring, and the sealing groove is used to fill the sealing ring. Multiple second jacking mechanisms are uniformly fixedly installed in a ring array on the outer wall of the wellbore; Multiple second push plates are uniformly fixedly installed in a ring array on the upper outer circumference of the bottom support plate. The upper end of the second push plate is inserted into the second push mechanism, which is used to adjust the insertion depth of the second push plate.

[0010] As a preferred technical solution of this application, a plurality of guide rods are uniformly fixedly installed at the bottom of the annular support groove, and the bottom of the well ring is provided with an integral protruding ring, which is inserted into the annular support groove. A plurality of positioning holes for the guide rods to be inserted are uniformly opened at the bottom of the protruding ring.

[0011] As a preferred technical solution of this application, the first jacking mechanism includes an L-shaped box, a first screw, and a drive gear assembly. The L-shaped box is fixedly installed on the inner side wall of the well shaft. The first screw and the drive gear assembly are rotatably installed in the L-shaped box. The lower end of the first jacking plate is provided with an integral lifting plate. The lifting plate is inserted into the L-shaped box. The surface of the lifting plate is provided with a first threaded hole. The first screw is connected to the first threaded hole. The drive gear assembly is used to drive the first screw to rotate and drive the lifting plate to rise and fall.

[0012] As a preferred technical solution of this application, the second jacking mechanism includes a limiting box and a second screw. The limiting box is fixedly installed at the lower end of the outer wall of the well. The upper end of the second jacking plate is inserted into the limiting box. The upper end of the second jacking plate is provided with a second threaded hole. The lower end of the second screw is connected to the second threaded hole. The upper end of the second screw passes through the upper part of the limiting box.

[0013] As a preferred technical solution of this application, the bottom of the annular support groove is evenly provided with multiple slots, the lower end of the first push plate is inserted into the corresponding slot, the L-shaped box is provided with a sliding groove on one side, the sliding groove is connected to the slot, and the lifting plate is located at the sliding groove position.

[0014] As a preferred technical solution of this application, the first screw is rotatably mounted in the L-shaped box via a bearing seat.

[0015] As a preferred technical solution of this application, the drive gear assembly includes a driving gear, a driven gear, and a rotating shaft. The driven gear is fixedly installed at the lower end of the first screw, the rotating shaft is rotatably installed at the outer end of the L-shaped box, the driving gear is fixedly installed at the lower end of the rotating shaft, and the driving gear meshes with the driven gear.

[0016] As a preferred technical solution of this application, the upper end of the rotating shaft passes through the L-shaped box, and a polygonal groove is provided at the upper end of the rotating shaft.

[0017] As a preferred technical solution of this application, the rotating shaft surface is fixedly provided with a ring rib, and a limiting sleeve is fixedly installed in the top of the L-shaped box, with the limiting sleeve engaging with the ring rib.

[0018] As a preferred technical solution of this application, a retaining ring is fixedly provided on the surface of the second screw, and a U-shaped card plate that is movably engaged with the retaining ring is fixedly installed on the inner side wall of the limiting box.

[0019] This invention achieves coarse adjustment in the initial stage of installation by setting multiple second jacking mechanisms between the well shaft and the bottom support plate, and adjusting the distance between the well shaft and the bottom support plate through the second jacking mechanisms; and achieves fine adjustment in the later stage of installation by setting multiple first jacking mechanisms between the well shaft and the well ring, and adjusting the relative height between the well ring and the well shaft through the first jacking mechanisms. The two-stage adjustment is independent of each other and can adapt to different site elevation deviations. When the manhole cover sinks due to foundation settlement, there is no need to excavate or remove it. Simply open the manhole cover and use a tool to rotate the shaft from above the manhole to lift the manhole cover to the design elevation, restoring the road surface to a flat state, which greatly reduces maintenance costs. The entire structure is made of precast concrete and purely mechanical components. On-site installation can be completed simply by hoisting, aligning, and rotating the screw. The installation process is simple and extends the service life. Attached Figure Description

[0020] Figure 1 This is a structural schematic diagram of a prefabricated, adjustable elevation manhole ring structure. Figure 2 An exploded view of the structure of a prefabricated, adjustable-elevation manhole ring; Figure 3 This is a structural diagram of the first jacking mechanism in a prefabricated, adjustable elevation manhole ring structure. Figure 4 This is a structural diagram of the second jacking mechanism in a prefabricated, adjustable elevation manhole ring structure. Figure 5 This is a structural diagram of the manhole ring in a prefabricated, adjustable-elevation manhole ring structure.

[0021] In the picture: 1. Well shaft; 11. Annular support groove; 12. Guide rod; 13. Slot opening; 14. Slide groove; 2. Bottom support plate; 21. Limiting ring; 22. Sealing groove; 3. Well ring; 31. Protruding ring; 32. Positioning hole; 4. Well cover; 5. First jacking mechanism; 51. L-shaped box; 52. First screw; 53. Bearing seat; 54. Driven gear; 55. Rotating shaft; 56. Driving gear; 57. Limiting sleeve; 58. Ring rib; 6. First jacking plate; 61. Lifting plate; 62. First threaded hole; 7. Second jacking mechanism; 71. Limiting box; 72. Second screw; 73. Retaining ring; 74. U-shaped clamping plate; 8. Second jacking plate; 81. Second threaded hole. Detailed Implementation

[0022] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] See Figures 1 to 5 As shown, the present invention provides a prefabricated adjustable elevation manhole ring structure, which includes a manhole ring 3, a manhole cylinder 1 and a bottom support plate 2 from top to bottom. A manhole cover 4 is movably hinged to one end of the manhole ring 3. It also includes multiple first jacking mechanisms 5, first jacking plates 6, second jacking mechanisms 7 and second jacking plates 8. Well shaft 1 is a precast reinforced concrete cylinder with a strength grade of C35; the upper end of the well shaft 1 is provided with an annular support groove 11, and the bottom of the well ring 3 is detachably installed in the annular support groove 11. Multiple first jacking mechanisms 5 are uniformly fixedly installed in a ring array on the inner side wall of the well barrel 1, and the first jacking mechanism 5 is located below the annular support groove 11; Multiple first push plates 6 are evenly and fixedly installed at the bottom of the well ring 3, and the first push mechanism 5 is used to adjust the height of the first push plate 6 at the corresponding position. The bottom support plate 2 is located at the bottom of the manhole ring 1. The bottom support plate 2 is a circular precast reinforced concrete slab with a strength grade of C30. The bottom support plate 2 is used to be placed directly on the compacted foundation at the bottom of the manhole pit as the load-bearing foundation of the entire inspection well. A limit ring 21 is fixedly installed on the upper part of the bottom support plate 2. The outer diameter of the limit ring 21 matches the inner diameter of the manhole 1. The limit ring 21 is a steel ring. The limit ring 21 is firmly connected to the bottom support plate 2 by pre-embedded bolts or welded anchor bars. The function of the limit ring 21 is: when the manhole 1 is placed on the bottom support plate 2, the limit ring 21 is inserted into the inner wall of the manhole 1 to radially limit the manhole 1 and prevent the manhole 1 from moving horizontally. A sealing groove 22 is provided at the upper edge of the limiting ring 21. The sealing groove 22 is used to fill the sealing ring. The sealing groove 22 is used to install the EPDM rubber sealing ring. After the well barrel 1 is pressed, the sealing ring undergoes elastic deformation to fill the gap between the well barrel 1 and the bottom support plate 2, preventing groundwater from seeping into the well. Multiple second jacking mechanisms 7 are uniformly fixedly installed in a ring array on the outer wall of the wellbore 1; Multiple second push plates 8 are uniformly fixedly installed in a ring array on the upper outer circumference of the bottom support plate 2. Specifically, the lower end of the second push plate 8 is fixed in the concrete of the bottom support plate 2 by welding or pre-embedding, and the upper end extends upward. The upper end of the second push plate 8 is inserted into the second push mechanism 7, which is used to adjust the insertion depth of the second push plate 8.

[0024] In this embodiment, a plurality of guide rods 12 are uniformly fixedly installed at the bottom of the annular support groove 11. The bottom of the well ring 3 is provided with an integral protruding ring 31, which is inserted into the annular support groove 11. A plurality of positioning holes 32 for the guide rods 12 to be inserted are uniformly opened at the bottom of the protruding ring 31. The guide rods 12 are stainless steel round bars with a diameter of 12mm. The function of the guide rods 12 is to be inserted into the positioning holes 32 at the bottom of the well ring 3 to perform circumferential positioning of the well ring 3 and prevent the well ring 3 from rotating in the annular support groove 11.

[0025] In this embodiment, the first pushing mechanism 5 includes an L-shaped box 51, a first screw 52, ​​and a drive gear assembly. The L-shaped box 51 is fixedly installed on the inner wall of the well shaft 1. The L-shaped box 51 is a welded steel part, in the shape of an inverted L. Its vertical section is fixed to the inner wall of the well shaft 1 by bolts, and its horizontal section is located below the slot opening 13. The first screw 52 and the drive gear assembly are rotatably installed in the L-shaped box 51. The L-shaped box 51 has a cavity inside to accommodate the first screw 52 and the lifting plate 61. The lower end of the first pushing plate 6 has an integral lifting plate 61. The lifting plate 61 is inserted into the L-shaped box 51. The surface of the lifting plate 61 has a first threaded hole 62. The first screw 52 is connected to the first threaded hole 62. The drive gear assembly is used to drive the first screw 52 to rotate, thereby driving the lifting plate 61 to rise and fall.

[0026] In this embodiment, the second jacking mechanism 7 includes a limiting box 71 (which corresponds to the position of the second jacking plate 8) and a second screw 72. The limiting box 71 is fixedly installed at the lower end of the outer wall of the well shaft 1. The bottom of the limiting box 71 is open for the upper end of the second jacking plate 8 to be inserted. The upper end of the second jacking plate 8 is provided with a second threaded hole 81. The lower end of the second screw 72 is connected to the second threaded hole 81. The top of the limiting box 71 is provided with a round hole. The upper end of the second screw 72 passes through the round hole at the top of the limiting box 71.

[0027] In this embodiment, the bottom of the annular support groove 11 is evenly provided with a plurality of slots 13, specifically four slots 13. The slots 13 are staggered from the guide rod 12. The slots 13 are rectangular through holes that penetrate the top concrete of the well shaft 1 and are used for the lower end of the first push plate 6 to pass through. At the corresponding position below the slots 13, an L-shaped box 51 of the first push mechanism 5 is fixedly installed on the inner side wall of the well shaft 1. The lower end of the first push plate 6 is inserted into the corresponding slot 13. A sliding groove 14 is provided on one side of the L-shaped box 51. The sliding groove 14 is connected to the slot 13. The lifting plate 61 is located at the position of the sliding groove 14.

[0028] In this embodiment, the first screw 52 is rotatably mounted inside the L-shaped box 51 via a bearing seat 53.

[0029] In this embodiment, the drive gear assembly includes a drive gear 56, a driven gear 54, and a rotating shaft 55. The driven gear 54 is fixedly installed at the lower end of the first screw 52, ​​the rotating shaft 55 is rotatably installed at the outer end of the L-shaped box 51, and the drive gear 56 is fixedly installed at the lower end of the rotating shaft 55. The drive gear 56 meshes with the driven gear 54.

[0030] In this embodiment, the upper end of the rotating shaft 55 passes through the L-shaped box 51, and a polygonal groove is provided at the upper end of the rotating shaft 55 so as to be rotated using a wrench.

[0031] In this embodiment, a ring rib 58 is fixedly provided on the surface of the rotating shaft 55, and a limiting sleeve 57 is fixedly installed at the top of the L-shaped box 51. The limiting sleeve 57 is movably engaged with the ring rib 58. The cooperation between the ring rib 58 and the limiting sleeve 57 restricts the upward axial movement of the rotating shaft 55, ensuring that the rotating shaft 55 can only rotate and cannot move up and down, thereby maintaining the correct meshing of the driving gear 56 and the driven gear 54.

[0032] In this embodiment, a retaining ring 73 is fixedly provided on the surface of the second screw 72, and a U-shaped clamping plate 74 that is movably engaged with the retaining ring 73 is fixedly installed on the inner side wall of the limiting box 71. The opening of the U-shaped clamping plate 74 faces the inside of the limiting box 71 and is used to clamp the retaining ring 73 on the second screw 72 to restrict the axial movement of the second screw 72.

[0033] The specific steps are as follows: Excavate a pit at the designated location, compact the bottom of the pit and pour a 100mm thick C15 plain concrete cushion layer, level and cure it. Hoist the bottom support plate 2 onto the padding layer and adjust its levelness (using a level instrument to measure) so that the horizontal error of the upper surface of the bottom support plate 2 is controlled within ±2mm; Install an EPDM sealing ring in the sealing groove 22 of the limiting ring 21 of the bottom support plate 2. The sealing ring should be flat and free from twisting. Lift the shaft 1 and slowly lower it into position so that the lower end of the shaft 1 is fitted onto the outside of the limiting ring 21 of the bottom support plate 2, while ensuring that the four second push plates 8 on the bottom support plate 2 are respectively aligned with the bottom openings of the four limiting boxes 71 on the outer side wall of the shaft 1. Slowly lower the shaft 1 until its lower end face contacts the upper surface of the bottom support plate 2. At this point, the upper end of the second push plate 8 has been inserted into the limiting box 71; Use a spirit level to check the levelness of the upper surface of the well casing 1. If it is not level, use a wrench to rotate each of the second screws 72. When rotating, because the retaining ring 73 is held in place by the U-shaped clamping plate 74, the second screw 72 cannot move up or down and can only rotate in place; the second threaded hole 81 on the second push plate 8 rotates relative to the second screw 72, causing the second push plate 8 to move up or down relative to the second screw 72. Since the second push plate 8 is fixed on the bottom support plate 2, the result of the relative movement is that the limit box 71 and the well casing 1 are lifted or lowered.

[0034] Repeat the measurement and adjustment until the upper end face of the well barrel 1 is horizontal and reaches the designed predetermined elevation (leaving a well ring adjustment margin, usually making the upper end face of the well barrel 30-50mm lower than the road surface design elevation), record the screwing depth of each second screw 72 to ensure that the four second push plates 8 are subjected to uniform force. After the height of the shaft 1 is adjusted, there may be a gap between the lower end face of the shaft 1 and the upper surface of the bottom support plate 2 (caused by the second push plate 8). High-strength non-shrink cement mortar is used to fill the gap to ensure that the shaft 1 sits stably on the bottom support plate 2. Take care to protect the sealing ring and prevent the mortar from entering the sealing groove. Check whether the annular support groove 11 at the upper end of the well shaft 1 is clean and whether the guide rod 12 is intact; Lift the well ring 3, align the protruding ring 31 at the bottom of the well ring 3 with the annular support groove 11 of the well barrel 1, and align the positioning hole 32 on the protruding ring 31 with the guide rod 12 in the annular support groove 11, and align the lower ends of the four first push plates 6 with the four slots 13 on the well barrel 1. Slowly lower the well ring 3 until the protruding ring 31 is completely inside the annular support groove 11. The guide rod 12 is inserted into the positioning hole 32. The lower end of the first push plate 6 passes through the slot opening 13 and enters the L-shaped box 51, and the lifting plate 61 falls into the sliding groove 14 of the L-shaped box 51. At this time, the first screw 52 has passed through the first threaded hole 62 of the lifting plate 61. Open the manhole cover 4, insert the Allen wrench into the upper hexagonal groove of the shaft 55 from the manhole opening; Rotating the Allen wrench causes the shaft 55 to rotate, which in turn drives the drive gear 56 to rotate. The drive gear 56 then drives the driven gear 54 and the first screw 52 to rotate. The first screw 52 drives the lifting plate 61 to move up and down along the slide groove 14 via a threaded connection. The lifting plate 61 drives the partial lifting and lowering of the first push plate 6 and the well ring 3. Use a precision level to measure the elevation of the upper surface of the manhole ring 3 (usually measuring four directional points), and adjust the rotating shafts 55 of the four first jacking mechanisms 5 respectively so that the elevation of each point on the upper surface of the manhole ring 3 reaches the road design elevation and the levelness error is ≤2mm.

[0035] After adjustment, reconfirm that the well ring 3 and well barrel 1 are in close contact and there is no shaking.

[0036] If the top surface of manhole ring 3 is found to be lower than the road surface (settlement exceeding 5mm), open manhole cover 4; Use an Allen wrench to rotate each shaft 55 in sequence. Rotating clockwise will raise the first push plate 6, thereby raising the well ring 3 to the design elevation. If the well casing 1 itself also experiences significant subsidence, the well casing 1 can be lifted as a whole using the second jacking mechanism 7, and then the well ring 3 can be finely adjusted using the first jacking mechanism 5. After the lifting is completed, check whether the connection between the manhole ring 3 and the surrounding road surface is smooth. If necessary, fill the gap between the bottom of the manhole ring 3 and the annular support groove 11 with thin shims to eliminate gaps.

[0037] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A prefabricated, adjustable-elevation manhole ring structure, comprising, from top to bottom, a manhole ring, a manhole casing, and a bottom support plate, wherein a manhole cover is movably hinged to one end of the manhole ring, characterized in that: It also includes multiple first jacking mechanisms, first jacking plates, second jacking mechanisms, and second jacking plates; The wellbore has an annular support groove at the upper end, and the bottom of the well ring is detachably installed in the annular support groove. Multiple first jacking mechanisms are uniformly fixedly installed in a ring array on the inner sidewall of the wellbore, and the first jacking mechanism is located below the ring support groove; Multiple first push plates are evenly and fixedly installed at the bottom of the well ring, and the first push mechanism is used to adjust the height of the first push plate at the corresponding position. The bottom support plate is located at the bottom of the well ring, and a limit ring is fixedly installed on the upper part of the bottom support plate. The outer diameter of the limit ring matches the inner diameter of the well ring. A sealing groove is provided at the upper edge of the limit ring, and the sealing groove is used to fill the sealing ring. Multiple second jacking mechanisms are uniformly fixedly installed in a ring array on the outer wall of the wellbore; Multiple second push plates are uniformly fixedly installed in a ring array on the upper outer circumference of the bottom support plate. The upper end of the second push plate is inserted into the second push mechanism, which is used to adjust the insertion depth of the second push plate.

2. The prefabricated, assembled, adjustable elevation manhole ring structure according to claim 1, characterized in that: Multiple guide rods are evenly fixedly installed at the bottom of the annular support groove. The bottom of the well ring is provided with an integral protruding ring that is inserted into the annular support groove. Multiple positioning holes for inserting guide rods are evenly opened at the bottom of the protruding ring.

3. The prefabricated, assembled, adjustable elevation manhole ring structure according to claim 1, characterized in that: The first jacking mechanism includes an L-shaped box, a first screw, and a drive gear assembly. The L-shaped box is fixedly installed on the inner side wall of the well shaft. The first screw and the drive gear assembly are rotatably installed inside the L-shaped box. The lower end of the first jacking plate is provided with an integral lifting plate, which is inserted into the L-shaped box. A first threaded hole is opened on the surface of the lifting plate. The first screw is connected to the first threaded hole. The drive gear assembly is used to drive the first screw to rotate, thereby driving the lifting plate to rise and fall.

4. The prefabricated, assembled, adjustable elevation manhole ring structure according to claim 1, characterized in that: The second jacking mechanism includes a limiting box and a second screw. The limiting box is fixedly installed at the lower end of the outer wall of the well. The upper end of the second jacking plate is inserted into the limiting box. The upper end of the second jacking plate has a second threaded hole. The lower end of the second screw is connected to the second threaded hole. The upper end of the second screw passes through the upper part of the limiting box.

5. The prefabricated, assembled, adjustable elevation manhole ring structure according to claim 2, characterized in that: The bottom of the annular support groove is evenly provided with multiple slots. The lower end of the first push plate is inserted into the corresponding slot. The L-shaped box is provided with a sliding groove on one side, which is connected to the slot. The lifting plate is located in the sliding groove.

6. The prefabricated, assembled, adjustable elevation manhole ring structure according to claim 3, characterized in that: The first screw is rotatably mounted inside the L-shaped box via a bearing seat.

7. The prefabricated, assembled, adjustable elevation manhole ring structure according to claim 3, characterized in that: The drive gear assembly includes a driving gear, a driven gear, and a rotating shaft. The driven gear is fixedly installed at the lower end of the first screw, the rotating shaft is rotatably installed at the outer end of the L-shaped box, and the driving gear is fixedly installed at the lower end of the rotating shaft. The driving gear meshes with the driven gear.

8. The prefabricated, assembled, adjustable elevation manhole ring structure according to claim 7, characterized in that: The upper end of the rotating shaft passes through the L-shaped box, and a polygonal groove is provided at the upper end of the rotating shaft.

9. The prefabricated, assembled, adjustable elevation manhole ring structure according to claim 8, characterized in that: The rotating shaft surface is fixedly provided with a ring rib, and a limiting sleeve is fixedly installed at the top of the L-shaped box, with the limiting sleeve engaging with the ring rib.

10. The prefabricated, assembled, adjustable elevation manhole ring structure according to claim 4, characterized in that: The second screw has a retaining ring fixedly mounted on its surface, and the inner side wall of the limiting box has a U-shaped card plate that engages with the retaining ring.

Images