A manhole cover repair and edge trimming device for municipal engineering

Abstract

The present invention discloses a manhole cover repair and trimming device for municipal engineering, which relates to the technical field of manhole cover trimming and grinding, and includes: a trimming table, which is arranged on the top of the ground; a trimming frame, which is fixedly installed on the front and rear walls of the trimming table; a grinding wheel, which is arranged on the top of the trimming table; a rotating device, which is fixedly installed on the top of the inner wall of the trimming table; a rotating frame, which is fixedly installed on the output end of the rotating device, and the rotating frame penetrates through the top of the trimming table; a cover body, which is arranged on the top of the rotating frame; a correction block, which is fixedly installed on the top of the rotating frame, and the correction block is used for positioning the cover body; through the contact between the correction block and the inner wall of the water inlet hole, the position of the cover body can be effectively restricted, ensuring the stability and consistency of the cover body during the trimming process, thereby improving the trimming accuracy, and the correction block contacts the inner wall of the water inlet hole and limits the cover body.

Description

Technical Field

[0001] The present invention relates to the technical field of manhole cover trimming and grinding, and specifically relates to a manhole cover repair and trimming device for municipal engineering. Background Art

[0002] The manhole cover repair and trimming device for municipal engineering usually consists of a trimming table, a rotating device, a pressing frame, a grinding wheel machine, etc., and the manhole cover repair and trimming operation usually repairs and trims manhole covers of the same size.

[0003] The patent with the patent announcement number CN213319479U relates to a manhole cover repair and trimming device for municipal engineering, belonging to the field of municipal engineering, including a circular top plate. The bottom end of the circular top plate is fixedly connected to the bottom end of a motor fixing frame, the inner surface of the motor fixing frame is fixedly connected to the outer surface of a motor, one end of a support long rod is rotationally connected to the circular top plate through a fixed short column, the bottom side of the other end of the support long rod is fixedly connected to the top end of a telescopic shock-absorbing rod, and the bottom end of the telescopic shock-absorbing rod is fixedly connected to the top end of a circular anti-slip gasket. In this patent, through the rotation of the output shaft driven by the motor, the motor output shaft drives the first bevel gear to rotate, the first bevel gear drives the second bevel gear to rotate, and the second bevel gear drives the cutting edge grinding wheel to rotate at a high speed through a transmission long rod, achieving the effect of quickly trimming the edge by pulling the force-bearing sleeve rod to rotate around the track ring for one week, solving the problems that the traditional manhole cover repair and trimming requires manual cutting, which is time-consuming and laborious, and the trimming is irregular, making subsequent maintenance difficult.

[0004] In the above patent, through the transmission long rod driving the cutting edge grinding wheel to rotate at a high speed, the effect of quickly trimming the edge by pulling the force-bearing sleeve rod to rotate around the track ring for one week is achieved, solving the problems that the traditional manhole cover repair and trimming requires manual cutting, which is time-consuming and laborious, and the trimming is irregular, making subsequent maintenance difficult. However, it is difficult to ensure that the manhole cover body is closely attached to the grinding wheel machine during the trimming operation. If the manhole cover body and the grinding wheel machine cannot be closely attached, the trimming accuracy will be affected, resulting in uneven trimming of the edge of the manhole cover body. Summary of the Invention

[0005] Aiming at the deficiencies of the prior art, the present invention provides a manhole cover repair and trimming device for municipal engineering, solving the problems raised in the above background art.

[0006] To achieve the above object, the present invention is realized through the following technical solutions: A manhole cover repair and trimming device for municipal engineering, comprising: a trimming table, the trimming table is arranged on the top of the ground; a trimming frame, the trimming frame is fixedly installed on the front and rear walls of the trimming table; a grinding wheel, the grinding wheel is arranged on the top of the trimming table; a rotating device, the rotating device is fixedly installed on the top of the inner wall of the trimming table; a rotating frame, the rotating frame is fixedly installed at the output end of the rotating device, and the rotating frame penetrates through the top of the trimming table; a cover body, the cover body is arranged on the top of the rotating frame; a correction block, the correction block is fixedly installed on the top of the rotating frame, and the correction block is used for positioning the cover body; a servo motor, the servo motor is fixedly installed on the top of the trimming frame; a lead screw, the lead screw is fixedly installed at the output end of the servo motor; a pressing rod, the pressing rod is slidably installed on the inner wall of the trimming frame, the pressing rod is threadedly connected with the lead screw, and the pressing rod is used for fixing the cover body; a pressing frame, the pressing frame rotatably penetrates through the top of the pressing rod, and the correction block contacts the inner wall of the water inlet hole and limits the cover body.

[0007] According to the above technical solution, a connecting rod is fixedly installed on the inner wall of the trimming frame, a connecting plate is slidably installed on the circumferential surface of the connecting rod, a connecting groove is opened at the rear side of the connecting plate, and the pressing frame moves downward to contact the top of the cover body and perform secondary fixation on the cover body.

[0008] According to the above technical solution, a first spring is arranged between the connecting rod and the connecting plate. The first spring can drive the connecting plate to reset. The connecting plate contacts the connecting plate. The pressing rod penetrates through the top of the trimming table. When the pressing rod cannot move downward continuously, an appropriate pressing force is maintained between the pressing frame and the cover body.

[0009] According to the above technical solution, a protection component for preventing the cover body from being directly taken out after trimming is arranged on the top of the inner wall of the trimming table. A limiting component is arranged on the top of the inner wall of the trimming table. The protection component includes a U-shaped rod, a T-shaped plate, a square hole, a support frame and a bearing plate. The U-shaped rod is fixedly installed on the top of the inner wall of the trimming table. The T-shaped plate is slidably installed on the circumferential surface of the U-shaped rod. The square hole is opened on the top of the trimming table. The support frame is slidably installed in the inner wall of the square hole. The bearing plate is fixedly installed in the inner wall of the square hole. A second spring is arranged between the support frame and the square hole. When the support frame moves upward, the support frame can fit with the side of the cover body when the cover body rotates and is trimmed.

[0010] According to the above technical solution, a rotating rod rotatably penetrates through the upper and lower walls of the bearing plate. A spiral groove is opened on the circumferential surface of the rotating rod. The support frame is slidably connected with the spiral groove. A load-bearing spring is arranged between the U-shaped rod and the T-shaped plate. The load-bearing spring can drive the T-shaped plate to reset.

[0011] According to the above technical solution, the front side of the T-shaped plate is set as an inclined surface, the bottom of the support frame is set as an inclined surface, the T-shaped plate contacts the bottom of the support frame, and the rotating rod can only rotate slowly so that the support frame can only move slowly downward.

[0012] According to the above technical solution, the limit assembly includes a butt joint tube, a piston rod and a limit plate, the butt joint tube is fixedly passed through the upper and lower walls of the load-bearing plate, the piston rod is slidably installed on the inner wall of the butt joint tube, the limit plate is slidably installed on the inner wall of the butt joint tube, a butt joint spring is arranged between the butt joint tube and the piston rod, the rear side of the limit plate is fixedly passed through the limit frame, the circumferential surface of the rotating frame is provided with a limit hole, mineral oil is arranged inside the butt joint tube, and the limit frame moves to the rear side to break away from the contact with the limit hole and release the limit on the rotating frame.

[0013] According to the above technical solution, an O-ring is arranged between the limit plate and the butt tube, and the sealing between the limit plate and the butt tube can be improved by the O-ring. The limit frame contacts the inner wall of the limit hole, and the bottom of the piston rod is set as an inclined surface.

[0014] The present invention provides a manhole cover repair and trimming device for municipal engineering, which has the following beneficial effects:

[0015] (1) The municipal engineering manhole cover repair and trimming device limits the position of the cover body by contacting the inner wall of the water inlet hole with the correction block. The contact between the correction block and the inner wall of the water inlet hole can effectively limit the position of the cover body, ensuring the stability and consistency of the cover body during the trimming process, thereby improving the trimming accuracy. The pressing frame moves downward to contact the top of the cover body and fixes the cover body for a second time. The secondary fixation of the cover body can effectively prevent the cover body from rebounding due to uneven force during the trimming process, thereby avoiding uneven cutting or trimming during the trimming process.

[0016] (2) The manhole cover repair and trimming device for municipal engineering can maintain an appropriate pressing force between the pressing frame and the cover body by preventing the pressing rod from moving further downward. By limiting the movement of the pressing rod, it can ensure that the pressure applied to the cover body is just right, thereby improving the accuracy of repair and trimming. In addition, the appropriate pressing force can protect the rotating equipment and avoid excessive use or overloading of the rotating equipment.

[0017] (3) The manhole cover repair and trimming device for municipal engineering uses a support frame to move upward so that the support frame can fit with the side of the cover body when the cover body is rotated for trimming. The fit between the support frame and the side of the cover body can reduce the shaking of the cover body during the rotational trimming process. The fit between the support frame and the side of the cover body can effectively scrape off the waste residue generated by the trimming, thereby improving the quality of the final trimming.

[0018] (4) For the manhole cover repair and trimming device for municipal engineering, the support frame slowly moves downward to disengage from the contact with the cover body, thus facilitating the removal of the cover body. If the cover body is removed immediately after the trimming operation, it will cause the trimmed surface to be uneven or deformed. By slowly disengaging from the support frame, the cover body can naturally cool and regain its shape without additional external forces, thereby avoiding unnecessary deformation.

[0019] (5) For the manhole cover repair and trimming device for municipal engineering, the limit frame moves backward to disengage from the contact with the limit hole and releases the limit on the rotating frame. By ensuring the stability of the cover body before releasing the limit on the rotating frame, the safety risk of the cover body slipping can be greatly reduced, ensuring the smooth progress of the trimming operation and protecting the safety of workers at the same time. Brief Description of the Drawings

[0020] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0021] Figure 2 It is a schematic semi-sectional structure diagram of the trimming table of the present invention;

[0022] Figure 3 For the present invention Figure 2 Schematic enlarged structure diagram of part A in;

[0023] Figure 4 It is a schematic structure diagram of the position of the rotating device and the rotating frame of the present invention;

[0024] Figure 5 It is a schematic structure diagram of the position of the bearing plate and the rotating rod of the present invention;

[0025] Figure 6 For the present invention Figure 5 Schematic enlarged structure diagram of part B in;

[0026] Figure 7 It is a schematic semi-sectional structure diagram of the docking pipe of the present invention.

[0027] In the figure: 1, trimming table; 2, trimming frame; 3, grinding wheel; 4, rotating device; 5, rotating frame; 6, correction block; 7, cover body; 8, servo motor; 9, lead screw; 10, pressing rod; 11, connecting rod; 12, connecting plate; 13, connecting groove; 14, pressing frame; 151, U-shaped rod; 152, T-shaped plate; 153, square hole; 154, support frame; 155, bearing plate; 156, rotating rod; 157, bearing spring; 161, docking pipe; 162, piston rod; 163, docking spring; 164, limit plate; 165, limit frame; 166, limit hole. Detailed Embodiments

[0028] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0029] Please refer to Figures 1-6 , an embodiment of the present invention is: a manhole cover repair and edge trimming device for municipal engineering, including: a trimming table 1, the trimming table 1 is arranged on the top of the ground; a trimming frame 2, the trimming frame 2 is fixedly installed on the front and rear walls of the trimming table 1; a grinding wheel 3, the grinding wheel 3 is arranged on the top of the trimming table 1; a rotating device 4, the rotating device 4 is fixedly installed on the top of the inner wall of the trimming table 1; a rotating frame 5, the rotating frame 5 is fixedly installed on the output end of the rotating device 4, and the rotating frame 5 penetrates through the top of the trimming table 1; a cover body 7, the cover body 7 is arranged on the top of the rotating frame 5; a correction block 6, the correction block 6 is fixedly installed on the top of the rotating frame 5, and the correction block 6 is used to position the cover body 7; a servo motor 8, the servo motor 8 is fixedly installed on the top of the trimming frame 2; a lead screw 9, the lead screw 9 is fixedly installed on the output end of the servo motor 8; a pressing rod 10, the pressing rod 10 is slidably installed on the inner wall of the trimming frame 2, the pressing rod 10 is threadedly connected with the lead screw 9, and the pressing rod 10 is used to fix the cover body 7; a pressing frame 14, the pressing frame 14 rotatably penetrates through the top of the pressing rod 10. By the contact between the correction block 6 and the inner wall of the water inlet hole, the position of the cover body 7 can be effectively restricted, ensuring the stability and consistency of the cover body 7 during the edge trimming process, thereby improving the accuracy of edge trimming.

[0030] A connecting rod 11 is fixedly installed on the inner wall of the trimming frame 2. A connecting plate 12 is slidably installed on the circumferential surface of the connecting rod 11. A connecting groove 13 is opened at the rear side of the connecting plate 12. The pressing frame 14 moves downward to contact the top of the cover body 7 and performs secondary fixation on the cover body 7. By the secondary fixation of the cover body 7, it can effectively prevent the cover body 7 from rebounding due to uneven force during the edge trimming process, thereby avoiding uneven cutting or trimming during the edge trimming process.

[0031] A first spring is arranged between the connecting rod 11 and the connecting plate 12. The first spring can drive the connecting plate 12 to reset. The connecting plate 12 contacts the connecting plate 12. The pressing rod 10 penetrates through the top of the trimming table 1. By restricting the movement of the pressing rod 10, it can ensure that the pressure applied to the cover body 7 is just right, and an appropriate pressing force can protect the rotating device 4, avoiding overuse or overload of the rotating device 4.

[0032] During the operation of this embodiment: After aligning the water inlet hole on the surface of the cover body 7 with the correction block 6, manually place the cover body 7 on the top of the rotating frame 5. After the cover body 7 is placed on the top of the rotating frame 5, the correction block 6 contacts the inner wall of the water inlet hole. The correction block 6 contacts the inner wall of the water inlet hole and positions the cover body 7. After the cover body 7 is positioned by the correction block 6, the servo motor 8 operates to drive the screw rod 9 to rotate. The rotation of the screw rod 9 squeezes the pressing rod 10. The pressing rod 10 moves downward under the action of the screw rod 9. The downward movement of the pressing rod 10 drives the pressing frame 14 to move downward. The downward movement of the pressing frame 14 contacts the top of the cover body 7 and secondarily fixes the cover body 7. At the same time, when the pressing rod 10 moves downward, it will align with the connecting groove 13. After the pressing rod 10 aligns with the connecting groove 13, the connecting plate 12 moves toward the cover body 7 under the elastic force of the first spring. The movement of the connecting plate 12 toward the cover body 7 causes the connecting groove 13 to contact the pressing rod 10. The contact between the connecting groove 13 and the pressing rod 10 causes the connecting plate 12 to position the pressing rod 10. The pressing rod 10 cannot continue to move downward under the limitation of the connecting plate 12. The inability of the pressing rod 10 to continue moving downward keeps an appropriate pressing force between the pressing frame 14 and the cover body 7. After an appropriate pressing force is maintained between the pressing frame 14 and the cover body 7, the rotating device 4 operates to drive the rotating frame 5 to rotate. The rotation of the rotating frame 5 drives the cover body 7 to rotate. At the same time, the grinding wheel 3 is started to perform trimming operations on the rotating cover body 7.

[0033] Please refer to Figures 1-7 , on the basis of the above embodiment, in another embodiment of the present invention, a protection component for preventing the cover body 7 from being directly taken out after trimming is provided on the inner wall top of the trimming table 1. A limiting component is provided on the inner wall top of the trimming table 1. The protection component includes a U-shaped rod 151, a T-shaped plate 152, a square hole 153, a support frame 154, and a bearing plate 155. The U-shaped rod 151 is fixedly installed on the inner wall top of the trimming table 1. The T-shaped plate 152 is slidably installed on the circumferential surface of the U-shaped rod 151. The square hole 153 is opened on the top of the trimming table 1. The support frame 154 is slidably installed on the inner wall of the square hole 153. The bearing plate 155 is fixedly installed on the inner wall of the square hole 153. A second spring is provided between the support frame 154 and the square hole 153. By fitting the support frame 154 to the side of the cover body 7, the shaking of the cover body 7 during the rotary trimming process can be reduced.

[0034] A rotating rod 156 rotatably penetrates the upper and lower walls of the bearing plate 155. A spiral groove is opened on the circumferential surface of the rotating rod 156. The support frame 154 is slidably connected to the spiral groove. A load-bearing spring 157 is provided between the U-shaped rod 151 and the T-shaped plate 152. The load-bearing spring 157 can drive the T-shaped plate 152 to reset. By fitting the support frame 154 to the side of the cover body 7, the waste residues generated during trimming can be effectively scraped off, thereby improving the quality of the final trimming.

[0035] The front side of the T-shaped plate 152 is set as an inclined surface, and the bottom of the support frame 154 is set as an inclined surface. The T-shaped plate 152 contacts the bottom of the support frame 154. The rotating rod 156 can only rotate slowly, so that the support frame 154 can only move downward slowly. By slowly disengaging from the contact with the support frame 154, the cover body 7 can be naturally cooled and restored to its shape without additional external force, thereby avoiding unnecessary deformation.

[0036] The limiting component includes a butt joint pipe 161, a piston rod 162 and a limiting plate 164. The butt joint pipe 161 is fixedly penetrated through the upper and lower walls of the load-bearing plate 155. The piston rod 162 is slidably installed on the inner wall of the butt joint pipe 161. The limiting plate 164 is slidably installed on the inner wall of the butt joint pipe 161. A butt joint spring 163 is arranged between the butt joint pipe 161 and the piston rod 162. A limiting frame 165 is fixedly penetrated through the rear side of the limiting plate 164. Limiting holes 166 are formed on the circumferential surface of the rotating frame 5. Mineral oil is arranged inside the butt joint pipe 161. By ensuring that the rotation frame 5 is released from the limit only after the cover body 7 is stabilized, the safety risk of the cover body 7 slipping can be greatly reduced, ensuring the smooth progress of the trimming operation.

[0037] An O-ring is arranged between the limiting plate 164 and the butt joint pipe 161. The sealing performance between the limiting plate 164 and the butt joint pipe 161 can be improved through the O-ring. The limiting frame 165 contacts the inner wall of the limiting hole 166. The bottom of the piston rod 162 is set as an inclined surface.

[0038] When this embodiment works: the pressing rod 10 moves downward to contact the inclined surface of the T-shaped plate 152 and extrude the T-shaped plate 152. The T-shaped plate 152 is extruded by the pressing rod 10 and moves towards the rotating device 4. The T-shaped plate 152 moves towards the rotating device 4 and pulls the load-bearing spring 157. The load-bearing spring 157 deforms and stores energy under the pulling of the T-shaped plate 152. At the same time, the T-shaped plate 152 moves towards the rotating device 4 and contacts the inclined surface of the support frame 154 and extrudes the support frame 154. The support frame 154 is extruded by the T-shaped plate 152 and moves upward. The support frame 154 moves upward and extrudes the second spring. The second spring deforms and stores energy under the extrusion of the support frame 154. At the same time, the upward movement of the support frame 154 enables the support frame 154 to fit with the side of the cover body 7 when the cover body 7 is rotationally trimmed. After the trimming operation of the cover body 7 is completed, the support frame 154 moves downward and resets under the elastic force of the second spring. The support frame 154 moves downward and resets to extrude the rotating rod 156. The rotating rod 156 can only rotate slowly under the extrusion of the support frame 154. The rotating rod 156 can only rotate slowly, so that the support frame 154 can only move downward slowly. The support frame 154 moves downward slowly and disengages from the contact with the cover body 7, thereby facilitating the removal of the cover body 7.

[0039] The support frame 154 moves upward to contact the piston rod 162 and extrude the piston rod 162. The piston rod 162 moves upward under the extrusion of the support frame 154. The piston rod 162 moves upward to extrude the docking spring 163. The docking spring 163 deforms and stores energy under the extrusion of the piston rod 162. At the same time, the piston rod 162 moves upward to extrude the mineral oil inside the docking pipe 161. The mineral oil inside the docking pipe 161 moves upward under the extrusion of the piston rod 162. The mineral oil moves upward to contact the limit plate 164 and extrude the limit plate 164. The limit plate 164 moves backward under the extrusion of the mineral oil. The backward movement of the limit plate 164 drives the limit frame 165 to move. The backward movement of the limit frame 165 disengages from the contact with the limit hole 166 and releases the limit on the rotating frame 5. After the limit on the rotating frame 5 is released, the rotating device 4 can drive the rotating frame 5 to rotate.

[0040] Although the embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that various changes, modifications, substitutions and alterations can be made therein without departing from the principles and spirit of the invention, and the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A manhole cover repair and trimming device for municipal engineering, characterized in that, Including: A trimming table (1), the trimming table (1) is arranged on top of the ground; A trimming frame (2), the trimming frame (2) is fixedly installed on the front and rear walls of the trimming table (1); A grinding wheel machine (3), the grinding wheel machine (3) is arranged on top of the trimming table (1); A rotating device (4), the rotating device (4) is fixedly installed on the top of the inner wall of the trimming table (1); A rotating frame (5), the rotating frame (5) is fixedly installed on the output end of the rotating device (4), and the rotating frame (5) penetrates through the top of the trimming table (1); A cover body (7), the cover body (7) is arranged on top of the rotating frame (5); A correction block (6), the correction block (6) is fixedly installed on top of the rotating frame (5), and the correction block (6) is used to position the cover body (7); A servo motor (8), the servo motor (8) is fixedly installed on top of the trimming frame (2); A lead screw (9), the lead screw (9) is fixedly installed on the output end of the servo motor (8); A pressing rod (10), the pressing rod (10) is slidably installed on the inner wall of the trimming frame (2), the pressing rod (10) is threadedly connected with the lead screw (9), and the pressing rod (10) is used to fix the cover body (7); A pressing frame (14), the pressing frame (14) rotatably penetrates through the top of the pressing rod (10).

2. The manhole cover repair and trimming device for municipal engineering according to claim 1, characterized in that: A connecting rod (11) is fixedly installed on the inner wall of the trimming frame (2), a connecting plate (12) is slidably installed on the circumferential surface of the connecting rod (11), and a connecting groove (13) is opened at the rear side of the connecting plate (12).

3. The manhole cover repair and edge trimming device for municipal engineering according to claim 2, characterized in that: A first spring is arranged between the connecting rod (11) and the connecting plate (12), the connecting plate (12) is in contact with the connecting plate (12), the pressing rod (10) penetrates through the top of the trimming table (1), a protection component is arranged on the top of the inner wall of the trimming table (1) for preventing the cover body (7) from being directly taken out after trimming, and a limiting component is arranged on the top of the inner wall of the trimming table (1).

4. A manhole cover repair and trimming device for municipal engineering according to claim 3, characterized in that: The protection component includes a U-shaped rod (151), a T-shaped plate (152), a square hole (153), a support frame (154) and a load-bearing plate (155). The U-shaped rod (151) is fixedly installed on the top of the inner wall of the trimming table (1), the T-shaped plate (152) is slidably installed on the circumferential surface of the U-shaped rod (151), the square hole (153) is opened on the top of the trimming table (1), the support frame (154) is slidably installed on the inner wall of the square hole (153), the load-bearing plate (155) is fixedly installed on the inner wall of the square hole (153), and a second spring is arranged between the support frame (154) and the square hole (153).

5. The manhole cover repair and edge trimming device for municipal engineering according to claim 4, characterized in that: A rotating rod (156) rotatably penetrates through the upper and lower walls of the load-bearing plate (155), a spiral groove is opened on the circumferential surface of the rotating rod (156), the support frame (154) is slidably connected with the spiral groove, and a load-bearing spring (157) is arranged between the U-shaped rod (151) and the T-shaped plate (152).

6. The manhole cover repair and edge trimming device for municipal engineering according to claim 5, characterized in that: The front side of the T-shaped plate (152) is set as an inclined surface, the bottom of the support frame (154) is set as an inclined surface, and the T-shaped plate (152) is in contact with the bottom of the support frame (154).

7. The manhole cover repair and edge trimming device for municipal engineering according to claim 6, characterized in that: The limiting component includes a docking pipe (161), a piston rod (162) and a limiting plate (164). The docking pipe (161) is fixedly penetrated through the upper and lower walls of the load-bearing plate (155). The piston rod (162) is slidably installed on the inner wall of the docking pipe (161). The limiting plate (164) is slidably installed on the inner wall of the docking pipe (161). A docking spring (163) is arranged between the docking pipe (161) and the piston rod (162). A limiting frame (165) is fixedly penetrated through the rear side of the limiting plate (164). A limiting hole (166) is formed on the circumferential surface of the rotating frame (5). Mineral oil is arranged inside the docking pipe (161).

8. A manhole cover repair and edge trimming device for municipal engineering according to claim 7, characterized in that: An O-ring is arranged between the limiting plate (164) and the docking pipe (161). The limiting frame (165) is in contact with the inner wall of the limiting hole (166). The bottom of the piston rod (162) is provided as an inclined surface.

Images