Tunnel grouting hole construction device with torque limiting function

Abstract

This invention relates to the technical field of tunnel construction, specifically a tunnel grouting hole construction device with torque limiting function. It includes a housing, with a drilling motor and a drill rod respectively mounted on both sides of the housing. A drive disc and a driven disc are positioned between the drilling motor and the drill rod. A spline sleeve is fixedly mounted on one side of the drive disc, and a spline shaft is slidably mounted inside the spline sleeve. The spline shaft is connected to the output end of the drilling motor, and the end of the spline shaft away from the drilling motor is slidably mounted inside the drive disc. A driven shaft is fixedly mounted on one side of the drive disc. An overload protection component is provided between the drive disc and the driven disc, and a braking component is located inside the housing. Through the braking component, after the drive disc disengages from the driven disc, the disc brake pads engage with the disc brake disc, achieving rapid braking of the driven shaft and the drill rod. This reduces the number of rotations of the drill rod under inertia, preventing damage caused by rotation under inertia.

Description

Technical Field

[0001] This invention relates to the technical field of tunnel construction, specifically a tunnel grouting hole construction device with torque limiting function. Background Technology

[0002] A torque limiter, also known as a safety clutch or safety coupling, is typically installed between the driving and driven sides of a power transmission system. When an overload fault occurs (torque exceeding a set value), the torque limiter disengages, effectively protecting the drive machinery (such as motors, reducers, and servo motors) and the load. Torque limiters are used in drilling motors for tunnel grouting holes to prevent damage caused by excessive torque during drilling.

[0003] In the existing technology, by connecting the driven plate and the driving plate, when the drilling motor drives the driving plate to rotate, the driving plate drives the driven plate to rotate, which in turn drives the drill rod to rotate, thus enabling the drilling operation of the grouting hole in the tunnel. When the drilling motor is subjected to a large torque, the driving plate disengages from the driven plate to avoid damage to the output shaft of the drilling motor due to excessive torque. When the driving plate disengages from the driven plate, the driven plate will still drive the drill rod to rotate due to inertia, and the rotation of the drill rod due to inertia may cause damage. Summary of the Invention

[0004] The purpose of this invention is to provide a tunnel grouting hole construction device with torque limiting function to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] A tunnel grouting hole construction device with torque limiting function includes a housing, on both sides of which a drilling motor and a drill rod are respectively arranged;

[0007] A drive disc and a driven disc are provided between the drilling motor and the drill rod. A spline sleeve is fixedly provided on one side of the drive disc. A spline shaft is slidably sleeved inside the spline sleeve. The spline shaft is connected to the output end of the drilling motor. The end of the spline shaft away from the drilling motor is slidably provided inside the drive disc. A driven shaft is fixedly provided on one side of the drive disc. The driven shaft is fixedly connected to the drill rod.

[0008] An overload protection component is provided between the active disc and the driven disc. When a large torque is generated during the operation of the drilling motor driving the drill rod, the active disc and the driven disc will disengage, thereby protecting the output shaft of the drilling motor. A braking component is provided inside the housing to quickly stop the driven shaft after the active disc and the driven disc disengage.

[0009] An annular seat is fixedly provided on the side of the driving disc away from the driven disc. A pushing component and a locking component are provided on the top and bottom of the housing. The pushing component cooperates with the annular seat to make the pushing component move synchronously with the driving disc. When the driving disc disengages from the driven disc, the pushing component acts on the locking component, thereby releasing the limiting position of the braking component and making the braking component act on the driven shaft.

[0010] As described above, the overload protection assembly includes a first spring, which is sleeved on the outside of the spline shaft and disposed between the side of the driving disc away from the driven disc and the inner wall of the housing. The side of the driving disc away from the spline sleeve is provided with a plurality of evenly distributed balls in an annular pattern, and the end of the driven disc away from the driven shaft is provided with a groove that mates with the balls.

[0011] As described above: the braking assembly includes a disc brake pad and a disc brake disc, as well as a mounting plate and a fixing plate sleeved on the outside of the driven shaft. The disc brake disc is fixedly disposed on the side of the driven disc away from the driving disc, the disc brake pad is fixedly disposed on the side of the mounting plate close to the driven disc, the fixing plate is fixedly connected to the inner wall of the housing, and a second spring is disposed between the mounting plate and the fixing plate.

[0012] As described above: the disc brake pad consists of four disc brake blocks, and the disc brake blocks have mounting holes inside. The mounting plate consists of two annular plates, which are fixedly connected by bolts. A locking bolt is fitted inside the mounting hole and passes through the annular plate. The disc brake block is fixedly mounted on one side of the mounting plate by the locking bolt.

[0013] As described above: spring seats are symmetrically fixed on opposite sides of the fixing plate and the mounting plate, and the second spring is disposed between the two opposite spring seats.

[0014] As described above, the pushing assembly includes a first bracket fixedly connected to the housing, a movable plate slidably disposed inside the first bracket, a push plate fixedly disposed at the bottom end of the movable plate near the snap-fit ​​assembly, a lifting block rotatably disposed at the end of the movable plate near the snap-fit ​​assembly, an annular groove formed inside the annular seat, and the end of the movable plate away from the push plate disposed inside the annular groove.

[0015] As described above: the snap-fit ​​assembly includes a second bracket fixedly connected to the housing, a lifting rod slidably disposed inside the second bracket, a wedge block fixedly disposed at the bottom of the lifting rod, a limiting plate fixedly disposed outside the lifting rod, a third spring disposed between the top of the limiting plate and the second bracket, a lifting block sleeved on the outside of the lifting rod and disposed at the bottom of the limiting plate, and limiting grooves that cooperate with the wedge block being opened at both the top and bottom of the mounting plate.

[0016] As described above, the lifting rod has raised strips on both its front and back sides.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows: During normal use, the active disc and the driven disc are connected and driven by the drilling motor, which in turn drives the drill rod to rotate and perform drilling operations for tunnel grouting holes. When the drilling motor transmits torque overload and the torque exceeds the set value, under the action of the overload protection component, the active disc moves to the side away from the driven disc. The active disc drives the spline sleeve to slide outside the spline shaft, and the active disc disengages from the driven disc and no longer drives the driven shaft, thus preventing damage to the device caused by excessive torque.

[0018] By using the braking components, after the driving disc and driven disc disengage, the disc brake pads cooperate with the disc brake disc to achieve the effect of rapid braking of the driven shaft and drill rod. This reduces the number of rotations of the drill rod under inertia, preventing damage caused by rotation under inertia. Furthermore, after prolonged use, if the disc brake pads wear to a certain extent or the elasticity of the second spring is poor, affecting the braking effect on the driven shaft, the disc brake pads and the second spring can be easily replaced.

[0019] By using a push component and a snap-fit ​​component, the braking component can brake the driven shaft as the driving disc disengages from the driven disc. Attached Figure Description

[0020] Figure 1 This is a front view of a tunnel grouting hole construction device with torque limiting function.

[0021] Figure 2 This is a schematic diagram of the internal structure of the outer shell of a tunnel grouting hole construction device with torque limiting function.

[0022] Figure 3 This is a schematic diagram of the connection between the driving and driven discs in a tunnel grouting hole construction device with torque limiting function.

[0023] Figure 4 This is a schematic diagram of the active disc in a tunnel grouting hole construction device with torque limiting function.

[0024] Figure 5 This is a schematic diagram of the driven disc in a tunnel grouting hole construction device with torque limiting function.

[0025] Figure 6 This is a schematic diagram of the braking component in a tunnel grouting hole construction device with torque limiting function.

[0026] Figure 7 This is a schematic diagram of the disc brake pads in a tunnel grouting hole construction device with torque limiting function.

[0027] Figure 8 This is a schematic diagram of the push assembly and snap-fit ​​assembly in a tunnel grouting hole construction device with torque limiting function.

[0028] In the diagram: 1. Housing; 2. Drilling motor; 3. Drill rod; 4. Driving disc; 5. Driven disc; 6. Spline sleeve; 7. Spline shaft; 8. Driven shaft; 9. Overload protection assembly; 91. First spring; 92. Ball bearing; 93. Groove; 10. Braking assembly; 101. Disc brake pad; 1011. Disc brake block; 1012. Mounting hole; 102. Disc brake disc; 103. Mounting plate; 1031. Annular plate; 1032. Locking bolt; 104. Fixing plate; 105. Second spring; 11. Annular seat; 12. Pushing assembly; 121. First bracket; 122. Moving plate; 123. Push plate; 124. Lifting block; 13. Snap-fit ​​assembly; 131. Second bracket; 132. Lifting rod; 133. Wedge block; 134. Limiting plate; 135. Third spring; 136. Limiting groove; 14. Spring seat. Detailed Implementation

[0029] Various exemplary embodiments, features, and aspects of this application will now be described in detail with reference to the accompanying drawings. The same reference numerals in the drawings denote elements that have the same or similar functions. Although various aspects of the embodiments are shown in the drawings, they are not necessarily drawn to scale unless specifically indicated otherwise.

[0030] The term “exemplary” as used herein means “serving as an example, embodiment, or illustration.” Any embodiment illustrated herein as “exemplary” is not necessarily to be construed as superior to or better than other embodiments.

[0031] Furthermore, to better illustrate this application, numerous specific details are provided in the following detailed embodiments. Those skilled in the art should understand that this application can be implemented even without certain specific details. In some instances, methods, means, and elements well-known to those skilled in the art have not been described in detail in order to highlight the main points of this application.

[0032] Please see Figure 1-8 In this embodiment of the invention, a tunnel grouting hole construction device with torque limiting function includes a housing 1, and a drilling motor 2 and a drill rod 3 are respectively arranged on both sides of the housing 1.

[0033] A drive disc 4 and a driven disc 5 are provided between the drilling motor 2 and the drill rod 3. A spline sleeve 6 is fixedly provided on one side of the drive disc 4. A spline shaft 7 is slidably sleeved inside the spline sleeve 6. The spline shaft 7 is connected to the output end of the drilling motor 2. The end of the spline shaft 7 away from the drilling motor 2 is slidably provided inside the drive disc 4. A driven shaft 8 is fixedly provided on one side of the drive disc 4. The driven shaft 8 is fixedly connected to the drill rod 3.

[0034] An overload protection component 9 is provided between the driving disc 4 and the driven disc 5. When a large torque is generated during the operation of the drilling motor 2 driving the drill rod 3, the driving disc 4 and the driven disc 5 are disengaged, thereby protecting the output shaft of the drilling motor 2. A braking component 10 is provided inside the housing 1 to quickly stop the driven shaft 8 after the driving disc 4 and the driven disc 5 are disengaged.

[0035] An annular seat 11 is fixedly provided on the side of the driving disc 4 away from the driven disc 5. The top and bottom of the housing 1 are provided with a pushing component 12 and a locking component 13. The pushing component 12 cooperates with the annular seat 11 to make the pushing component 12 move synchronously with the driving disc 4. When the driving disc 4 disengages from the driven disc 5, the pushing component 12 acts on the locking component 13, thereby releasing the limit of the braking component 10 and making the braking component 10 act on the driven shaft 8.

[0036] During normal use, the active disk 4 and the driven disk 5 are connected and driven by the drilling motor 2, which in turn drives the drill rod 3 to rotate for drilling grouting holes in the tunnel. When the drilling motor 2 is overloaded and the torque exceeds the set value, the active disk 4 moves away from the driven disk 5 under the action of the overload protection component 9. The active disk 4 drives the spline sleeve 6 to slide outside the spline shaft 7. The active disk 4 disengages from the driven disk 5 and no longer drives the driven shaft 8. At this time, the driven disk 5 drives the driven shaft 8 and the drill rod 3 to rotate freely due to inertia, preventing damage to the device caused by excessive torque.

[0037] With the braking assembly 10 in place, after the driving disc 4 is disengaged from the driven disc 5, the braking assembly 10 quickly brakes the driven shaft 8 to prevent the driven shaft 8 from continuing to drive the drill rod 3 to rotate due to inertia after the driving disc 4 is disengaged from the driven disc 5, thus avoiding damage to the drill rod 3 caused by inertial rotation.

[0038] When the driving disc 4 moves away from the driven disc 5, the driving component 12 drives the annular seat 11 on one side to move synchronously. The annular seat 11 acts on the driving component 12, and the driving component 12 acts on the locking component 13, thereby releasing the limit of the braking component 10, so that the braking component 10 acts on the driven shaft 8 to brake the driven shaft 8. After the driving disc 4 and the driven disc 5 are reconnected, the locking component 13 fixes the position of the braking component 10 again.

[0039] Please see Figure 2-5 The overload protection component 9 includes a first spring 91, which is sleeved on the outside of the spline shaft 7 and located between the side of the driving disk 4 away from the driven disk 5 and the inner wall of the outer casing 1. The side of the driving disk 4 away from the spline sleeve 6 is provided with a number of evenly distributed balls 92 in an annular shape. The end of the driven disk 5 away from the driven shaft 8 is provided with a groove 93 that cooperates with the balls 92.

[0040] When torque overload occurs, the ball bearings 92 on the drive disc 4 and the groove 93 on the driven disc 5 cannot withstand the torque. The ball bearings 92 will slide out of the groove 93, and the drive disc 4 will drive the spline sleeve 6 to slide along the spline shaft 7 away from the driven disc 5. At the same time, it will compress the first spring 91. At this time, the drive disc 4 and the driven disc 5 will disengage, and the drilling motor 2 will no longer transmit torque, so it will not drive the driven shaft 8 to drive the drill rod 3 to rotate, thus avoiding damage to the device caused by torque overload. When the torque returns to normal, under the action of the first spring 91, the drive disc 4 will be pushed closer to the driven disc 5. As the drive disc 4 rotates, the ball bearings 92 will re-engage inside the groove 93. At this time, the drilling motor 2 can drive the driven shaft 8 and the drill rod 3 to work again.

[0041] Please see Figure 2 , Figure 3 , Figures 5-7 The braking assembly 10 includes a disc brake pad 101 and a disc brake disc 102, as well as a mounting plate 103 and a fixing plate 104 sleeved on the outside of the driven shaft 8. The disc brake disc 102 is fixedly disposed on the side of the driven disc 5 away from the driving disc 4, and the disc brake pad 101 is fixedly disposed on the side of the mounting plate 103 close to the driven disc 5. The fixing plate 104 is fixedly connected to the inner wall of the housing 1, and a second spring 105 is disposed between the mounting plate 103 and the fixing plate 104.

[0042] When the driving disc 4 moves away from the driven disc 5, the locking assembly 13 releases the limit on the braking assembly 10. At this time, the mounting plate 103, under the action of the second spring 105, drives the disc brake pad 101 to move to one side of the driven disc 5. The cooperation between the disc brake pad 101 and the disc brake disc 102 achieves the effect of rapid braking of the driven shaft 8 and the drill rod 3, thereby reducing the number of rotations of the drill rod 3 under the action of inertia and preventing damage caused by the rotation of the drill rod 3 under the action of inertia.

[0043] The disc brake pad 101 is composed of four disc brake blocks 1011, and the disc brake blocks 1011 have mounting holes 1012 inside. The mounting plate 103 is composed of two annular plates 1031, which are fixedly connected by bolts. A locking bolt 1032 is fitted inside the mounting hole 1012 and passes through the annular plate 1031. The disc brake blocks 1011 are fixedly mounted on one side of the mounting plate 103 by the locking bolt 1032.

[0044] Spring seats 14 are symmetrically fixed on opposite sides of the fixing plate 104 and the mounting plate 103, and the second spring 105 is disposed between the two opposite spring seats 14.

[0045] When installing the disc brake pads 101, firstly, two annular plates 1031 are fitted onto the outside of the driven shaft 8 and fixed with bolts to form the mounting plate 103. Then, a second spring 105 is placed between two opposing spring seats 14. There are at least two second springs 105, and each second spring 105 has a spring seat 14 at both ends. Next, the mounting plate 103 is pushed, and the position of the mounting plate 103 is limited by the snap-fit ​​assembly 13. Then, four disc brake pads 1011 are sequentially installed in the annular plates 1031. When installing the disc brake pads 1011, locking bolts 1032 are inserted into the mounting holes 1012 and then passed through the annular plates. At the corresponding position of 1031, the disc brake block 1011 can be fixed with the nut. After long-term use, if the disc brake block 1011 is worn to a certain extent or the elasticity of the second spring 105 is poor, affecting the braking effect on the driven shaft 8, the disc brake block 1011 and the second spring 105 can be easily replaced. When replacing the disc brake block 1011, simply remove the locking bolt 1032 and install the new disc brake block 1011 on one side of the mounting plate 103. When replacing the second spring 105, by moving the snap-fit ​​component 13 outward to release the restriction on the mounting plate 103, the mounting plate 103 can be slid along the driven shaft 8, and the second spring 105 can be replaced.

[0046] Please see Figure 3 and Figure 8 The pushing component 12 includes a first bracket 121 fixedly connected to the outer shell 1. A movable plate 122 is slidably disposed inside the first bracket 121. A push plate 123 is fixedly disposed at the bottom of the movable plate 122 near the end of the snap-fit ​​component 13. A lifting block 124 is rotatably disposed at the end of the movable plate 122 near the snap-fit ​​component 13. An annular groove is formed inside the annular seat 11. The end of the movable plate 122 away from the push plate 123 is disposed inside the annular groove.

[0047] The snap-fit ​​assembly 13 includes a second bracket 131 fixedly connected to the outer shell 1. A lifting rod 132 is slidably arranged inside the second bracket 131. The front and back of the lifting rod 132 are both formed with protrusions. The protrusions prevent the lifting rod 132 from rotating. A wedge block 133 is fixedly arranged at the bottom of the lifting rod 132. A limit plate 134 is fixedly arranged outside the lifting rod 132. A third spring 135 is arranged between the top of the limit plate 134 and the second bracket 131. A lifting block 124 is sleeved on the outside of the lifting rod 132 and is arranged at the bottom of the limit plate 134. The top and bottom of the mounting plate 103 are both provided with limit grooves 136 that cooperate with the wedge block 133.

[0048] When the driving disc 4 disengages from the driven disc 5, it drives the annular seat 11 on one side to move synchronously. Since one end of the moving plate 122 is inside the annular groove in the annular seat 11, the moving plate 122 slides synchronously inside the first bracket 121 as the annular seat 11 moves, and drives the push plate 123 to move. The push plate 123 gradually moves away from the disc brake pad 101. As the moving plate 122 moves, it pulls the lifting block 124 outward. The lifting block 124 drives the limiting plate 134 and the lifting rod 132 outward. The limiting plate 134 squeezes the third spring 135. At this time, the wedge block 133 moves outward and disengages from the limiting groove 136 in the mounting plate 103. At this time, the limiting of the mounting plate 103 can be released, and the braking assembly 10 brakes the driven shaft 8. When the driving disc 4 resets and the driven disc 5 rejoins... During connection, the annular seat 11 resets, thereby resetting the moving plate 122. The moving plate 122 drives the push plate 123 to move synchronously. The push plate 123 exerts a thrust on the end of the mounting plate 103, causing the mounting plate 103 to drive the disc brake pad 101 to reset. During the resetting process of the mounting plate 103, a force is generated on the wedge block 133. The wedge block 133 is forced to move the lifting rod 132 and the limiting plate 134 outward. The third spring 135 is compressed. When the limiting groove 136 in the mounting plate 103 corresponds to the wedge block 133, the wedge block 133 is inserted into the limiting groove 136 under the action of the third spring 135, thus re-fixing the position of the braking assembly 10. Through the provided pushing assembly 12 and locking assembly 13, the braking assembly 10 can brake the driven shaft 8 as the driving disc 4 and the driven disc 5 disengage.

[0049] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0050] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A tunnel grouting hole construction device with torque limiting function, comprising a housing (1), characterized in that, A drilling motor (2) and a drill rod (3) are respectively provided on both sides of the outer casing (1); A drive disk (4) and a driven disk (5) are provided between the drilling motor (2) and the drill rod (3). A spline sleeve (6) is fixedly provided on one side of the drive disk (4). A spline shaft (7) is slidably sleeved inside the spline sleeve (6). The spline shaft (7) is connected to the output end of the drilling motor (2). The end of the spline shaft (7) away from the drilling motor (2) is slidably provided inside the drive disk (4). A driven shaft (8) is fixedly provided on one side of the drive disk (4). The driven shaft (8) is fixedly connected to the drill rod (3). An overload protection component (9) is provided between the active disk (4) and the driven disk (5) to disengage the active disk (4) and the driven disk (5) when the drilling motor (2) generates a large torque during the operation of the drill rod (3), thereby protecting the output shaft of the drilling motor (2). A braking component (10) is provided inside the housing (1) to quickly stop the driven shaft (8) after the active disk (4) and the driven disk (5) disengage. An annular seat (11) is fixedly provided on the side of the active disc (4) away from the driven disc (5). A pushing component (12) and a snap-fit ​​component (13) are provided on the top and bottom of the outer shell (1). The pushing component (12) cooperates with the annular seat (11) to make the pushing component (12) move synchronously with the active disc (4). When the active disc (4) disengages from the driven disc (5), the pushing component (12) acts on the snap-fit ​​component (13), thereby releasing the limit of the braking component (10) and making the braking component (10) act on the driven shaft (8). The overload protection component (9) includes a first spring (91), which is sleeved on the outside of the spline shaft (7) and located between the side of the driving disk (4) away from the driven disk (5) and the inner wall of the outer shell (1). The side of the driving disk (4) away from the spline sleeve (6) is provided with a plurality of evenly distributed balls (92) in an annular shape. The end of the driven disk (5) away from the driven shaft (8) is provided with a groove (93) that cooperates with the balls (92). The braking assembly (10) includes a disc brake pad (101) and a disc brake disc (102), as well as a mounting plate (103) and a fixing plate (104) sleeved on the outside of the driven shaft (8). The disc brake disc (102) is fixedly disposed on the side of the driven disc (5) away from the driving disc (4). The disc brake pad (101) is fixedly disposed on the side of the mounting plate (103) close to the driven disc (5). The fixing plate (104) is fixedly connected to the inner wall of the outer shell (1). A second spring (105) is disposed between the mounting plate (103) and the fixing plate (104). The pushing component (12) includes a first bracket (121) fixedly connected to the outer shell (1). A movable plate (122) is slidably disposed inside the first bracket (121). A push plate (123) is fixedly disposed at one end of the movable plate (122) near the snap-fit ​​component (13). A lifting block (124) is rotatably disposed at one end of the movable plate (122) near the snap-fit ​​component (13). An annular groove is formed inside the annular seat (11). One end of the movable plate (122) away from the push plate (123) is disposed inside the annular groove. The snap-fit ​​assembly (13) includes a second bracket (131) fixedly connected to the outer shell (1). A lifting rod (132) is slidably arranged inside the second bracket (131). A wedge block (133) is fixedly arranged at the bottom of the lifting rod (132). A limiting plate (134) is fixedly arranged outside the lifting rod (132). A third spring (135) is arranged between the top of the limiting plate (134) and the second bracket (131). The lifting block (124) is sleeved on the outside of the lifting rod (132) and is arranged at the bottom of the limiting plate (134). The top and bottom of the mounting plate (103) are provided with limiting grooves (136) that cooperate with the wedge block (133).

2. The tunnel grouting hole construction device with torque limiting function according to claim 1, characterized in that, The disc brake pad (101) is composed of four disc brake blocks (1011), and the disc brake blocks (1011) have mounting holes (1012) inside. The mounting plate (103) is composed of two annular plates (1031), which are fixedly connected by bolts. The mounting holes (1012) are fitted with locking bolts (1032), which penetrate the annular plates (1031). The disc brake blocks (1011) are fixedly mounted on one side of the mounting plate (103) by the locking bolts (1032).

3. The tunnel grouting hole construction device with torque limiting function according to claim 1, characterized in that, Spring seats (14) are symmetrically fixed on opposite sides of the fixing plate (104) and the mounting plate (103), and the second spring (105) is disposed between the two opposite spring seats (14).

4. A tunnel grouting hole construction device with torque limiting function according to claim 1, characterized in that, The lifting rod (132) has raised strips on both the front and back sides.

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