Prestressed steel cylinder concrete pipe turnover device

Abstract

The invention relates to the technical field of prestressed concrete cylinder pipe production and construction, and discloses a prestressed concrete cylinder pipe turnover device which comprises a base, and a base table is fixedly connected to one side of the base; the clamping assembly comprises a supporting frame and two clamping pieces, and the two clamping pieces are arranged at the two ends of the supporting frame correspondingly; the overturning assembly comprises a rotating base, an overturning piece and a connecting piece, an overturning groove is formed in the base table, the overturning piece is rotationally connected into the overturning groove, the rotating base rotates in the overturning groove through the overturning piece, one end of the supporting frame is fixedly connected to the top end of the rotating base, and a supporting rod is fixedly connected to the base; the connecting piece is arranged at the top end of the supporting rod and connected with the other end of the supporting frame. And the buffering assembly comprises a first buffering piece and a second buffering piece, the first buffering piece is connected with the base station, and the second buffering piece makes contact with the prestressed concrete cylinder pipe. According to the overturning device, stable overturning in the construction process of the prestressed steel cylinder concrete pipe is guaranteed, and damage to the prestressed steel cylinder concrete pipe is avoided while the efficiency is improved.

Description

Technical Field

[0001] The invention relates to the technical field of production and construction of prestressed steel cylinder concrete pipes, in particular to a prestressed steel cylinder concrete pipe turning device. Background Art

[0002] Prestressed steel cylinder concrete pipe refers to a water pipe made by winding circumferential prestressed steel wire on a high-strength concrete pipe core with a steel cylinder, and then spraying a dense cement mortar protective layer on it. It is a composite pipe composed of thin steel plate, high-strength steel wire and concrete. It fully and comprehensively exerts the tensile strength and easy sealing of steel and the compressive and corrosion resistance of concrete, and has the characteristics of high sealing, high strength and high impermeability.

[0003] Prestressed steel cylinder concrete pipes are usually in an upright state after production. During transportation and installation, the erected prestressed steel cylinder concrete pipes need to be laid flat. However, prestressed steel cylinder concrete pipes are large in size and heavy in weight, and special equipment and skilled operators are required for flipping. At present, the main method is to use a crane to lift the upper end and gradually flip it over. This method is not only inefficient, but also improper operation or equipment failure may cause the pipeline to collide with the ground, other objects or equipment, causing damage to the outer wall of the pipeline or the inner lining steel cylinder. At the same time, prestressed steel cylinder concrete pipes have a certain rigidity and weight. If the force is uneven or exceeds its bearing capacity during flipping, it may cause deformation of the pipeline structure, such as bulging, dents, etc., affecting the performance of the pipeline. In addition, during the flipping of prestressed steel cylinder concrete pipes, if safety measures are not in place or the operator is negligent, it may cause safety accidents such as pipeline falling and personal injury.

[0004] Therefore, there is an urgent need for a prestressed steel cylinder concrete pipe turning device to solve the above problems. Summary of the invention

[0005] The purpose of the present invention is to provide a prestressed steel cylinder concrete pipe turning device to solve the problems existing in the above-mentioned prior art.

[0006] To achieve the above object, the present invention provides the following solution: The present invention provides a prestressed steel cylinder concrete pipe turning device, comprising:

[0007] A base, wherein one side of the top of the base is fixedly connected to a base platform;

[0008] The clamping assembly comprises a support frame and two clamping members, wherein the support frame is arranged on the base, and the two clamping members are respectively arranged at two ends of the support frame, and the two clamping members are respectively used to clamp two ends of the steel cylinder concrete pipe;

[0009] The flip assembly comprises a rotating base, a flip member and a connecting member, wherein a flip groove is provided on the base, the flip member is rotatably connected in the flip groove, the rotating base rotates in the flip groove through the flip member, one end of the support frame is fixedly connected to the top of the rotating base, a support rod is fixedly connected to the base, and the connecting member is arranged at the top of the support rod and connected to the other end of the support frame;

[0010] The buffer assembly comprises a first buffer and a second buffer. The first buffer is arranged on the rotating base and connected to the base, and the second buffer is arranged on the base and contacts the steel cylinder concrete pipe.

[0011] Preferably, a plurality of first slide grooves are provided at equal intervals along the circumferential direction at both ends of the support frame, the clamping member comprises a first sliding block slidably connected in the first slide groove, the first sliding block is provided with a second slide groove, two clamping plates are slidably connected in the second slide groove, the two clamping plates are in contact with the outer wall and the inner wall of the steel cylinder concrete pipe respectively, and driving members are provided at both ends of the support frame, the first sliding block and the two clamping plates are respectively transmission-connected to the driving member.

[0012] Preferably, the driving member includes a threaded rod rotatably connected in the first sliding groove and a bidirectional threaded rod rotatably connected in the second sliding groove, the first sliding block is threadedly connected to the threaded rod, and the two clamping plates are respectively threadedly connected to both ends of the bidirectional threaded rod, and cavities are opened in both ends of the support frame, one end of the bidirectional threaded rod is fixedly connected to one end of the telescopic rod, the other end of the telescopic rod and one end of the threaded rod both extend into the cavity and are fixedly connected to the first bevel gear, two motors are fixedly connected in the cavity, and the second bevel gear is fixedly connected to the output shafts of the two motors, and the first bevel gear on the telescopic rod and the first bevel gear on the threaded rod are respectively meshed with the two second bevel gears.

[0013] Preferably, a groove is provided in the flip groove, and the flip member includes a rotating shaft rotatably connected to the groove, a first gear is fixedly connected to the rotating shaft, a first tooth plate is fixedly connected to the bottom end of the rotating base, the first tooth plate is located in the groove and meshes with the first gear, a control member is provided in the base, and the rotating shaft is transmission-connected to the control member.

[0014] Preferably, the control component includes a first hydraulic cylinder fixedly connected to both ends of the base, the telescopic ends of the two first hydraulic cylinders are fixedly connected to a second gear plate, the two ends of the rotating shaft respectively extend into the base and are fixedly connected to a second gear, and the second gear is meshed with the second gear plate.

[0015] Preferably, the connecting member includes a winding box fixedly connected to the top of the support rod, a winding roller is provided in the winding box, one end of the steel wire rope is fixedly connected to the winding roller, and the other end of the steel wire rope extends out of the winding box and is fixedly connected to the top of the support frame.

[0016] Preferably, guide grooves are provided on both side walls of the rotating base, the first buffer member includes a spring with one end fixedly connected to the inner wall of the guide groove, and cylinders are fixedly connected to both side walls of the flip groove, and the cylinders extend into the guide groove and are fixedly connected to the other end of the spring.

[0017] Preferably, the second buffer member comprises a second hydraulic cylinder hinged on the top of the base, a buffer plate is hinged on the telescopic end of the second hydraulic cylinder, and the buffer plate is in contact with the outer wall of the steel cylinder concrete pipe.

[0018] Preferably, two support columns are fixedly connected to the top of the base, and a support plate is fixedly connected to the top of the support column, and the support plate is used to support the steel cylinder concrete pipe.

[0019] Preferably, the cross-section of the turnover groove is a semicircular structure.

[0020] Compared with the prior art, the present invention has the following advantages and technical effects:

[0021] The present invention provides a prestressed steel cylinder concrete pipe flipping device, wherein two clamping members are used to clamp the top and bottom of the steel cylinder concrete pipe respectively, and after clamping, the rotating base is driven to rotate in the flipping groove by the provided flipping member, and at the same time, the connecting member is connected to the top of the support frame for placement, so as to ensure the stability of the flipping of the steel cylinder concrete pipe, realize the flipping of the steel cylinder concrete pipe, and further ensure the stability of the steel cylinder concrete pipe during the flipping process by the provided first buffer member and the second buffer member. The present invention has a simple structure and is convenient to operate, and ensures the stable flipping of the steel cylinder concrete pipe, improves efficiency and avoids damage to the steel cylinder concrete pipe. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative labor:

[0023] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0024] Figure 2 It is a cross-sectional view of the base and the support frame of the present invention;

[0025] Figure 3This is a schematic diagram of the control structure of the present invention;

[0026] Figure 4 This is a schematic diagram of the internal structure of the winding box of the present invention;

[0027] Figure 5 This is a schematic diagram of the loading state in the second embodiment of the present invention;

[0028] Among them, 1. base; 2. base; 3. support frame; 4. steel tube concrete pipe; 5. rotating base; 6. support rod; 7. first slide groove; 8. first slider; 9. second slide groove; 10. clamping plate; 11. threaded rod; 12. bidirectional threaded rod; 13. telescopic rod; 14. first bevel gear; 15. motor; 16. second bevel gear; 17. groove; 18. rotating shaft; 19. first gear; 20. first tooth plate; 21. first hydraulic cylinder; 22. second tooth plate; 23. second gear; 24. winding box; 25. winding roller; 26. wire rope; 27. guide groove; 28. spring; 29. ​​cylinder; 30. hydraulic cylinder; 31. buffer plate; 32. support column; 33. support plate. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0031] Embodiment 1:

[0032] Reference Figure 1-Figure 4 The present invention provides a prestressed steel cylinder concrete pipe turning device, comprising:

[0033] A base 1, with a base 2 fixedly connected to one side of the top of the base 1;

[0034] The clamping assembly includes a support frame 3 and two clamping members, wherein the support frame 3 is arranged on the base 2, and the two clamping members are respectively arranged at two ends of the support frame 3, and the two clamping members are respectively used to clamp two ends of the steel cylinder concrete pipe 4;

[0035] The flip assembly includes a rotating base 5, a flip member and a connecting member. A flip groove is provided on the base 2. The flip member is rotatably connected in the flip groove. The rotating base 5 rotates in the flip groove through the flip member. One end of the support frame 3 is fixedly connected to the top of the rotating base 5. A support rod 6 is fixedly connected to the base 1. The connecting member is arranged at the top of the support rod 6 and connected to the other end of the support frame 3.

[0036] The buffer assembly includes a first buffer and a second buffer. The first buffer is arranged on the rotating base 5 and connected to the base 2 , and the second buffer is arranged on the base 1 and contacts the steel cylinder concrete pipe 4 .

[0037] A further optimized solution is that a plurality of first slide grooves 7 are provided at equal intervals along the circumferential direction at both ends of the support frame 3, the clamping member includes a first slider 8 slidably connected in the first slide groove 7, a second slide groove 9 is provided on the first slider 8, two clamping plates 10 are slidably connected in the second slide groove 9, the two clamping plates 10 are in contact with the outer wall and the inner wall of the steel cylinder concrete pipe 4 respectively, and driving members are provided at both ends of the support frame 3, the first slider 8 and the two clamping plates 10 are respectively connected to the driving member by transmission.

[0038] Reference Figure 2 The first slider 8 is set to slide in the first slide groove 7 to adjust the position of the clamping plate 10 to make it compatible with the steel cylinder concrete pipe 4 of corresponding size. After the adjustment is completed, the clamping plate 10 is adjusted to slide in the second slide groove 9 to achieve the clamping of the steel cylinder concrete pipe 4 wall by the two clamping plates 10.

[0039] Specifically, the clamping plate 10 can be set as a retractable structure, that is, to ensure that the two clamping plates 10 can be placed on the outer wall and inner wall of the steel tube concrete pipe 4 respectively. The specific retractable plate is the existing technology and has the retractable function, which will not be described in detail here.

[0040] A further optimized solution is provided, wherein the driving member includes a threaded rod 11 rotatably connected to the first slide groove 7 and a bidirectional threaded rod 12 rotatably connected to the second slide groove 9, the first slider 8 is threadedly connected to the threaded rod 11, and the two clamping plates 10 are respectively threadedly connected to the two ends of the bidirectional threaded rod 12, and cavities are provided inside both ends of the support frame 3, one end of the bidirectional threaded rod 12 is fixedly connected to one end of a telescopic rod 13, the other end of the telescopic rod 13 and one end of the threaded rod 11 are both extended into the cavity and fixedly connected to a first bevel gear 14, two motors 15 are fixedly connected in the cavity, and second bevel gears 16 are fixedly connected to the output shafts of the two motors 15, and the first bevel gear 14 on the telescopic rod 13 and the first bevel gear 14 on the threaded rod 11 are respectively meshed with the two second bevel gears 16.

[0041] Reference Figure 2The motor 15 is provided to drive the second bevel gear 16 to rotate, and when the second bevel gear 16 rotates, it drives the first bevel gear 14 to rotate. When the first bevel gear 14 rotates, it drives the corresponding threaded rod 11 to rotate, thereby adjusting the position of the first slider 8. When the corresponding telescopic rod 13 rotates, it drives the bidirectional threaded rod 12 to rotate, thereby realizing the adjustment of the position of the two clamping plates 10.

[0042] Specifically, the telescopic rod 13 is two socketed square tubes, one of which is fixedly connected to the bidirectional threaded rod 12, and the other is rotated on the inner wall of the cavity and fixedly connected to the first bevel gear 14, thereby ensuring that it has a length adjustment function and can also ensure that it can rotate synchronously with the second bevel gear 16.

[0043] A further optimized solution is provided in the flip groove, and the flip member includes a rotating shaft 18 rotatably connected in the groove 17, a first gear 19 is fixedly connected to the rotating shaft 18, a first tooth plate 20 is fixedly connected to the bottom end of the rotating base 5, the first tooth plate 20 is located in the groove 17 and meshes with the first gear 19, a control member is provided in the base 2, and the rotating shaft 18 is transmission-connected to the control member.

[0044] Reference Figure 2 The first gear 19 is meshed with the first tooth plate 20. When the first gear 19 rotates, the meshed first tooth plate 20 drives the rotating base 5 to rotate in the turning groove, thereby driving the steel cylinder concrete pipe 4 to turn over.

[0045] A further optimized solution is that the control component includes a first hydraulic cylinder 21 fixedly connected to both ends of the base 2, the telescopic ends of the two first hydraulic cylinders 21 are fixedly connected to the second tooth plate 22, and the two ends of the rotating shaft 18 respectively extend into the base 2 and are fixedly connected to the second gear 23, and the second gear 23 is meshed with the second tooth plate 22.

[0046] Reference Figure 3 The second gear plate 22 is driven to move by the first hydraulic cylinder 21, and the second gear plate 22 drives the meshing second gear 23 to rotate when it moves, so that the first gear 19 is driven to rotate by the second gear 23 to realize the control of the first gear 19.

[0047] A further optimized solution is that the connecting part includes a winding box 24 fixedly connected to the top of the support rod 6, a winding roller 25 is arranged in the winding box 24, one end of the wire rope 26 is fixedly connected to the winding roller 25, and the other end of the wire rope 26 extends out of the winding box 24 and is fixedly connected to the top of the support frame 3.

[0048] Reference Figure 1 , Figure 4 , connected to the support frame 3 through the set steel wire rope 26, during the overturning process of the steel cylinder concrete pipe 4, the connection of the steel wire rope 26 ensures the stability of the overturning process of the steel cylinder concrete pipe 4.

[0049] To further optimize the solution, guide grooves 27 are provided on both side walls of the rotating base 5, the first buffer member includes a spring 28 with one end fixedly connected to the inner wall of the guide groove 27, and cylinders 29 are fixedly connected to both side walls of the flip groove, and the cylinders 29 extend into the guide groove 27 and are fixedly connected to the other end of the spring 28.

[0050] Reference Figure 2 The guide groove 27 is an arc-shaped guide groove, and its shape is adapted to the flipping trajectory of the rotating base 5. When the rotating base 5 rotates, the spring 28 is squeezed between the inner wall of the guide groove 27 and the cylinder 29. The spring 28 plays a partial buffering role, thereby ensuring the stability of the flipped steel cylinder concrete pipe 4.

[0051] According to a further optimized solution, the second buffer member includes a second hydraulic cylinder 30 hinged on the top of the base 1 , and a buffer plate 31 is hinged on the telescopic end of the second hydraulic cylinder 30 , and the buffer plate 31 contacts the outer wall of the steel tube concrete pipe 4 .

[0052] Reference Figure 1 The second hydraulic cylinder 30 is provided to drive the buffer plate 31 to contact the steel cylinder concrete pipe 4, thereby further supporting the steel cylinder concrete pipe 4 during the flipping process and ensuring its stable flipping.

[0053] According to a further optimized solution, two support columns 32 are fixedly connected to the top of the base 1 , and a support plate 33 is fixedly connected to the top of the support column 32 . The support plate 33 is used to support the steel tube concrete pipe 4 .

[0054] Reference Figure 1 The support plate 33 is used to support the overturned steel cylinder concrete pipe 4. At the same time, it is an arc-shaped structure, which is adapted to the outer wall shape of the steel cylinder concrete pipe 4, and the height is adapted to the height of the steel cylinder concrete pipe 4 after the overturn.

[0055] According to the further optimized solution, the cross section of the flip groove is a semicircular structure.

[0056] Reference Figure 2 The turning groove is a semicircular structure, and the corresponding rotating base 5 is also a semicircular structure adapted to the turning groove. The rotating base 5 turns 90 degrees in the turning groove to turn the steel cylinder concrete pipe 4 from a vertical state to a horizontal state.

[0057] Embodiment 2:

[0058] Reference Figure 5 The support frame 3 and the rotating base 5 are split structures, and a scissor-type telescopic device is installed on the top of the rotating base 5. The support frame 3 is driven away from the rotating base 5 by the scissor-type telescopic device.

[0059] To further optimize the solution, a number of moving rollers are installed on the inner wall of the support plate 33, and the moving rollers are in contact with the steel cylinder concrete pipe 4. When the steel cylinder concrete pipe 4 is placed horizontally, the steel cylinder concrete pipe 4 is driven to move on the moving rollers through the scissor-type telescopic device. At the same time, a transport vehicle is parked on one side of the device, and the steel cylinder concrete pipe 4 is pushed into the transport vehicle through the scissor-type telescopic device. After loading is completed, the support frame 3 is removed from the steel cylinder concrete pipe 4, and the steel cylinder concrete pipe 4 is transported to the construction site by the transport vehicle.

[0060] In one embodiment of the present invention, the specific number and height of the pallets 33 and the horizontal conveying height of the entire device are adapted to the transport vehicle.

[0061] In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0062] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A prestressed steel cylinder concrete pipe turning device, characterized in that: include: A base (1), wherein a top side of the base (1) is fixedly connected to a base platform (2); A clamping assembly, comprising a support frame (3) and two clamping members, wherein the support frame (3) is arranged on the base (2), and the two clamping members are respectively arranged at two ends of the support frame (3), and the two clamping members are respectively used to clamp two ends of the steel cylinder concrete pipe (4); A turning assembly comprises a rotating base (5), a turning piece and a connecting piece, wherein a turning groove is provided on the base (2), the turning piece is rotatably connected in the turning groove, the rotating base (5) is rotated in the turning groove through the turning piece, one end of the support frame (3) is fixedly connected to the top of the rotating base (5), a supporting rod (6) is fixedly connected to the base (1), and the connecting piece is arranged at the top of the supporting rod (6) and connected to the other end of the supporting frame (3); The buffer assembly comprises a first buffer component and a second buffer component, wherein the first buffer component is arranged on the rotating base (5) and connected to the base (2), and the second buffer component is arranged on the base (1) and contacts the steel cylinder concrete pipe (4).

2. The prestressed steel cylinder concrete pipe turning device according to claim 1 is characterized in that: A plurality of first slide grooves (7) are respectively provided at both ends of the support frame (3) at equal intervals along the circumferential direction; the clamping member comprises a first sliding block (8) slidably connected in the first slide groove (7); a second slide groove (9) is provided on the first sliding block (8); two clamping plates (10) are slidably connected in the second slide groove (9); the two clamping plates (10) are respectively in contact with the outer wall and the inner wall of the steel cylinder concrete pipe (4); a driving member is provided at both ends of the support frame (3); the first sliding block (8) and the two clamping plates (10) are respectively in transmission connection with the driving member.

3. The prestressed steel cylinder concrete pipe turning device according to claim 2 is characterized in that: The driving member comprises a threaded rod (11) rotatably connected in the first sliding groove (7) and a bidirectional threaded rod (12) rotatably connected in the second sliding groove (9); the first sliding block (8) is threadedly connected to the threaded rod (11); the two clamping plates (10) are respectively threadedly connected to the two ends of the bidirectional threaded rod (12); cavities are provided inside the two ends of the support frame (3); one end of the bidirectional threaded rod (12) is fixedly connected to one end of a telescopic rod (13); the other end of the telescopic rod (13) and one end of the threaded rod (11) are both extended into the cavity and fixedly connected to a first bevel gear (14); two motors (15) are fixedly connected in the cavity; the output shafts of the two motors (15) are fixedly connected to a second bevel gear (16); the first bevel gear (14) on the telescopic rod (13) and the first bevel gear (14) on the threaded rod (11) are respectively meshed with the two second bevel gears (16).

4. The prestressed steel cylinder concrete pipe turning device according to claim 1 is characterized in that: A groove (17) is provided in the flip groove, the flip member comprises a rotating shaft (18) rotatably connected in the groove (17), a first gear (19) is fixedly connected to the rotating shaft (18), a first tooth plate (20) is fixedly connected to the bottom end of the rotating base (5), the first tooth plate (20) is located in the groove (17) and meshes with the first gear (19), a control member is provided in the base (2), and the rotating shaft (18) is transmission-connected to the control member.

5. The prestressed steel cylinder concrete pipe turning device according to claim 4 is characterized in that: The control component comprises a first hydraulic cylinder (21) fixedly connected to the two ends of the base (2), the telescopic ends of the two first hydraulic cylinders (21) are fixedly connected to a second toothed plate (22), the two ends of the rotating shaft (18) respectively extend into the base (2) and are fixedly connected to a second gear (23), and the second gear (23) is meshed with the second geared plate (22).

6. The prestressed steel cylinder concrete pipe turning device according to claim 1 is characterized in that: The connecting member comprises a winding box (24) fixedly connected to the top end of the support rod (6), a winding roller (25) is arranged in the winding box (24), one end of a steel wire rope (26) is fixedly connected to the winding roller (25), and the other end of the steel wire rope (26) extends out of the winding box (24) and is fixedly connected to the top end of the support frame (3).

7. The prestressed steel cylinder concrete pipe turning device according to claim 2 is characterized in that: Guide grooves (27) are provided on both side walls of the rotating base (5); the first buffer member comprises a spring (28) having one end fixedly connected to the inner wall of the guide groove (27); cylinders (29) are fixedly connected to both side walls of the flip groove; the cylinders (29) extend into the guide groove (27) and are fixedly connected to the other end of the spring (28).

8. The prestressed steel cylinder concrete pipe turning device according to claim 1 is characterized by: The second buffer member comprises a second hydraulic cylinder (30) hingedly connected to the top of the base (1); a buffer plate (31) is hingedly connected to the telescopic end of the second hydraulic cylinder (30); and the buffer plate (31) is in contact with the outer wall of the steel cylinder concrete pipe (4).

9. The prestressed steel cylinder concrete pipe turning device according to claim 1, characterized in that: Two support columns (32) are fixedly connected to the top of the base (1), and a support plate (33) is fixedly connected to the top of the support column (32). The support plate (33) is used to support the steel cylinder concrete pipe (4).

10. The prestressed steel cylinder concrete pipe turning device according to claim 1, characterized in that: The cross section of the turnover groove is a semicircular structure.

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