Road traffic engineering pavement quality detection device

Abstract

The invention relates to the technical field of road surface quality detection, in particular to a road traffic engineering road surface quality detection device which comprises a detection device and a mounting frame, the mounting frame is mounted on the side face of the detection device, a detection mechanism is arranged in the detection device, and the detection mechanism comprises a marking unit and a sweeping unit. The marking unit is installed in the detection device, and the sweeping unit is installed at the front end of the detection device. According to the road surface quality detection device for the road traffic engineering, in the moving process of the device, a contact wheel is attached to a road surface in real time, when the road surface is uneven and concavo-convex, a moving rod is driven by the contact wheel to ascend and descend in a limiting cylinder, then a sealing plate is driven by a connecting rod to move, and then marking liquid is released; the to-be-overhauled area is accurately marked, the problem that the defect degree cannot be quantified in a traditional marking mode is solved, and the overhaul pertinence is improved.

Description

Technical Field

[0001] This invention relates to the field of pavement quality testing technology, specifically to a pavement quality testing device for highway traffic engineering. Background Technology

[0002] As a core component of transportation infrastructure, highway engineering encompasses key aspects of the entire lifecycle of highway structures, including surveying, measurement, design, construction, maintenance, and management. Its structural system is highly diversified, encompassing not only main structures such as roadbeds, pavements, bridges, culverts, and tunnels, but also functional supporting facilities such as drainage systems, safety protection facilities, landscaping, and traffic monitoring facilities, as well as service facilities such as buildings and workshops that support construction, maintenance, and monitoring work. Together, these constitute a complete system ensuring the safe and efficient operation of highways.

[0003] In the highway construction process, the quality acceptance after pavement paving is a crucial step in determining whether the project can be put into use, directly affecting the road's traffic safety and service life. Current technical inspection methods mostly rely on manual inspection, often using handheld marking cans. Traditional manual inspection, which depends on inspectors walking or driving at low speeds to observe and combine with simple tools for measurement, has significant limitations: First, the inspection efficiency is extremely low, covering only 3-5 kilometers per day. For road networks of thousands of kilometers in large cities, comprehensive inspection often takes several months, and labor costs account for more than 40% of the total maintenance budget. Second, when manually marking locations, it is impossible to use different types of markings based on the degree of unevenness of the ground. In daily road maintenance and defect detection, accurate marking of pavement potholes, subsidence, and other uneven defects is a critical prerequisite for subsequent repair work.

[0004] Currently, most road defect marking devices widely used in the industry locate defects by applying fixed-width lines or using a single type of marker. This type of marking method has a core functional limitation: the marking width and shape are preset fixed values, failing to adapt to the actual depth of potholes or the degree of unevenness in the road surface. For minor depressions only a few millimeters deep and severe potholes exceeding 20mm in depth, or road protrusions with varying heights, using the same width of line or uniform marking format fails to visually reflect the severity of the defect.

[0005] Based on the problems mentioned above, we propose a road surface quality testing device for highway traffic engineering to solve these problems. Summary of the Invention

[0006] The purpose of this invention is to provide a road surface quality testing device for highway traffic engineering, so as to solve the problems mentioned in the background art.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a road surface quality testing device for highway traffic engineering, comprising a testing device and a mounting frame, wherein the mounting frame is installed on the side of the testing device, and a testing mechanism is provided inside the testing device, wherein the testing mechanism includes a marking unit and a cleaning unit, wherein the marking unit is installed inside the testing device, and the cleaning unit is installed at the front end of the testing device; The marking unit includes a marking liquid storage tank, which is installed above the detection device. An L-shaped bracket is fixedly connected to the top of the detection device. The L-shaped bracket has a central shaft, and a rotating rod is movably connected to the outer surface of the central shaft. A traction rod is connected to the other end of the rotating rod, and a baffle is connected to the other end of the traction rod. A slide rail is provided on the top surface inside the detection device. A transfer box is provided inside the detection device, and a discharge pipe is connected to the side of the transfer box. A support shell is provided at the bottom of the detection device and on the outer surface of the discharge pipe. A moving groove is provided inside the support shell, and a sealing plate is movably connected inside the moving groove. A connecting rod is fixedly connected to the side of the sealing plate. A limiting cylinder is provided inside the detection device, and a moving rod is movably connected inside the limiting cylinder. A contact wheel is provided at the bottom of the moving rod, and a connecting plate is connected to the center of the contact wheel via a rotating shaft. The connecting plate is connected to the connecting rod.

[0008] Preferably, the transfer box is provided with a material guide slope inside.

[0009] Preferably, the baffle moves inside the slide rail, and a discharge port is provided inside the baffle.

[0010] Preferably, the detection device is provided with mounting brackets on both sides, a buffer device is provided at the bottom of the mounting brackets, an electric drive wheel is connected to the other end of the buffer device, and a steering power wheel assembly is provided at the center of the bottom front end of the detection device.

[0011] Preferably, the cleaning unit includes a blocking cover, which is fixedly connected to the front end of the detection device. A dual-output shaft drive motor is installed inside the detection device. The output shaft of the dual-output shaft drive motor is connected to a transmission shaft. A bevel gear transmission assembly two is connected to the side of the transmission shaft. An output shaft is connected to the front of the bevel gear transmission assembly two. A fixed cylinder is provided on the outer surface of the output shaft. The fixed cylinder is fixedly connected to the inside of the detection device. A rotating disk is fixedly connected to the end of the output shaft away from the bevel gear transmission assembly two. A connecting shaft is movably connected inside the rotating disk. A limit rod is fixedly connected to the outer surface of the fixed cylinder. A flipping shaft is movably connected inside the limit rod. A connecting seat is movably connected to the outer surface of the flipping shaft. A cleaning plate is fixedly connected to the side of the connecting seat. A fixed rod is fixedly connected to the inner side of the end of the connecting seat away from the cleaning plate. The connecting shaft is movable on the outer surface of the fixed rod.

[0012] Preferably, a drive belt assembly is driven to the outer surface of the drive shaft and located outside the detection device. A rotating shaft is driven to the other end of the drive belt assembly. A bevel gear drive assembly is driven to the other end of the rotating shaft. A stirring shaft is driven to the lower end of the bevel gear drive assembly and located inside the marking liquid storage tank.

[0013] Preferably, an infrared positioning and recording device is provided inside the detection device and at the front end of the moving rod.

[0014] Preferably, a spring is provided at the top of the limiting cylinder and on the outer surface of the moving rod.

[0015] Compared with the prior art, the beneficial effects of the present invention are: 1. This road surface quality inspection device for highway traffic engineering, through the installation of a marking unit, adds marking liquid into the marking liquid storage tank. During the movement of the inspection device, contact wheels contact the ground. When the road surface is uneven or has potholes, the contact wheels drive a moving rod to move up and down inside a limiting cylinder. As the contact wheels move, they pull a connecting rod via a connecting plate, causing the connecting rod to move a sealing plate on the outer surface of the moving trough. This releases the locking mechanism at the bottom of the discharge pipe, allowing the marking liquid to be released. Depending on the height and depth of the area, the moving rod rises or falls, controlling the distance the sealing plate is pulled and thus the width of the marking liquid release mark. This alerts workers to inspect the marked area.

[0016] 2. This road surface quality inspection device for highway traffic engineering, by installing a sweeping unit, uses a blocking cover to push larger objects to both sides, preventing interference with the normal operation of the device. For smaller particles and stones, a dual-output shaft drive motor is activated, which in turn drives the output shaft through a bevel gear transmission assembly to rotate. The output shaft then drives a rotating disk to rotate, causing the connecting shaft to extend and retract within the rotating disk. This controls the connecting seat, causing the sweeping plate to repeatedly rotate around the tilting shaft, thus cleaning dust and stones from the road surface along the device's path, preventing interference with the device's normal inspection and marking functions. 3. The road surface quality testing device for highway traffic engineering starts up with a dual-output shaft drive motor, which drives the rotating shaft to rotate via a transmission belt assembly. Then, through a bevel gear transmission assembly, the stirring shaft stirs the marking liquid inside the marking liquid storage tank, preventing the marking liquid from solidifying due to prolonged static conditions, which would affect the normal testing and marking process. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic diagram of the bottom structure of the present invention; Figure 3 This is a cross-sectional view of the internal structure of the detection device of the present invention; Figure 4 This is a schematic diagram of the main parts of the testing mechanism of the present invention; Figure 5 This is a cross-sectional view of the internal structure of the transfer box of the present invention; Figure 6 This is a schematic diagram of the cleaning unit structure of the present invention; Figure 7 This is a cross-sectional view of the marking unit part of the present invention.

[0019] In the diagram: 1. Detection device; 2. Mounting frame; 3. Buffer device; 4. Electric drive wheel; 5. Steering power wheel assembly; 6. Baffle cover; 7. Dual output shaft drive motor; 8. Transmission shaft; 9. Transmission belt assembly; 10. Rotating shaft; 11. Bevel gear transmission assembly one; 12. Marking liquid storage tank; 13. Stirring shaft; 14. Transfer box; 15. L-bracket; 16. Central shaft; 17. Rotating rod; 18. Traction rod; 19. Baffle; 20. Slide rail; 21. Discharge port ; 22. Guide slope; 23. Discharge pipe; 24. Support shell; 25. Sealing plate; 26. Moving groove; 27. Connecting rod; 28. Limiting cylinder; 29. ​​Moving rod; 30. Contact wheel; 31. Connecting plate; 32. Infrared positioning and recording device; 33. Bevel gear transmission assembly II; 34. Output shaft; 35. Fixed cylinder; 36. Rotating disk; 37. Limiting rod; 38. Tilting shaft; 39. Connecting seat; 40. Cleaning plate; 41. Fixed rod; 42. Connecting shaft. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0022] Please see Figures 1-7 The present invention provides a technical solution: a road surface quality testing device for highway traffic engineering, including a testing device 1 and a mounting frame 2. The mounting frame 2 is installed on the side of the testing device 1. The testing device 1 is provided with a testing mechanism, which includes a marking unit and a cleaning unit. The marking unit is installed inside the testing device 1, and the cleaning unit is installed at the front end of the testing device 1. The marking unit includes a marking liquid storage tank 12, which is installed above the detection device 1. An L-shaped bracket 15 is fixedly connected to the top of the detection device 1. The L-shaped bracket 15 has a central shaft 16, and a rotating rod 17 is movably connected to the outer surface of the central shaft 16. A traction rod 18 is connected to the other end of the rotating rod 17, and a baffle 19 is connected to the other end of the traction rod 18. A slide rail 20 is provided on the top surface inside the detection device 1. A transfer box 14 is provided inside the detection device 1, and a discharge pipe 23 is connected to the side of the transfer box 14. A support housing 24 is provided at the bottom of the detection device 1 and on the outer surface of the discharge pipe 23. A moving groove 26 is provided inside the support housing 24, and a sealing plate 25 is movably connected inside the moving groove 26. A connecting rod 27 is fixedly connected to the side of the sealing plate 25. A limit cylinder 28 is provided inside the detection device 1, and a moving rod 29 is movably connected inside the limit cylinder 28. A contact wheel 30 is provided at the bottom end of the moving rod 29. A connecting plate 31 is connected to a pivot at the center of wheel 30. The connecting plate 31 is connected to the connecting rod 27. Then, by installing a marking unit, the marking liquid is added into the marking liquid storage tank 12. Then, during the movement of the detection device 1, the contact wheel 30 contacts the ground. When the road surface is uneven or there are potholes, the contact wheel 30 drives the moving rod 29 to move up and down inside the limiting cylinder 28. Then, when the contact wheel 30 moves, it pulls the connecting rod 27 through the connecting plate 31. Then, the connecting rod 27 drives the sealing plate 25 to move on the outer surface of the moving groove 26, thereby releasing the lock on the bottom of the discharge pipe 23 to release the marking liquid. Then, depending on the height and depth of the location, the moving rod 29 rises or falls, thereby controlling the distance the sealing plate 25 is pulled, thus controlling the width of the marking liquid release mark, which can remind the staff to inspect the marking position in that area.

[0023] The transfer box 14 is equipped with a guide slope 22. The marker liquid that is transferred to the transfer box 14 through the marker liquid storage tank 12 is guided by the guide slope 22 and then gathers at the front end of the transfer box 14, so as to facilitate the collection and transfer to the inside of the discharge pipe 23.

[0024] The baffle 19 moves inside the slide rail 20. The baffle 19 has a discharge port 21 inside. When the device is transported to the designated position, the rotating rod 17 is flipped, which pushes the traction rod 18, thereby moving the baffle 19 on the slide rail 20. The baffle 19 blocks the transfer pipe of the marking liquid storage tank 12. When road quality testing is required, the rotating rod 17 drives the traction rod 18, which aligns the discharge port 21 inside the baffle 19 with the outlet of the transfer pipe, allowing the marking liquid to be transferred from the marking liquid storage tank 12 to the inside of the transfer box 14.

[0025] The detection device 1 is provided with mounting brackets 2 on both sides, and a buffer device 3 is provided at the bottom of the mounting bracket 2. The other end of the buffer device 3 is connected to an electric drive wheel 4. A steering power wheel assembly 5 is provided at the center of the bottom front end of the detection device 1. The buffer device 3 and the electric drive wheel 4 simultaneously provide power to drive the detection device 1. The device is steered by the steering power wheel assembly 5. The buffer device 3 further reduces the vibration caused by the road surface, thereby avoiding interference with the normal operation of the marking unit.

[0026] The cleaning unit includes a baffle 6, which is fixedly connected to the front end of the detection device 1. A dual-output shaft drive motor 7 is installed inside the detection device 1. The output shaft of the dual-output shaft drive motor 7 is driven by a drive shaft 8. A bevel gear transmission assembly 33 is driven by the side of the drive shaft 8. An output shaft 34 is driven by the front of the bevel gear transmission assembly 33. A fixed cylinder 35 is installed on the outer surface of the output shaft 34 and is fixedly connected inside the detection device 1. A rotating disk 36 is fixedly connected to the end of the output shaft 34 away from the bevel gear transmission assembly 33. A connecting shaft 42 is movably connected inside the rotating disk 36. A limit rod 37 is fixedly connected to the outer surface of the fixed cylinder 35. A tilting shaft 38 is movably connected inside the limit rod 37. A connecting seat 39 is movably connected to the outer surface of the tilting shaft 38. A cleaning plate 4 is fixedly connected to the side of the connecting seat 39. A fixed rod 41 is fixedly connected to the inner side of the end of the connecting seat 39 away from the sweeping plate 40. The connecting shaft 42 moves on the outer surface of the fixed rod 41. Then, by installing the sweeping unit, the blocking cover 6 pushes larger objects to both sides to avoid affecting the normal operation of the device. At the same time, for smaller particles, stones, etc., the dual output shaft drive motor 7 is started, which then drives the transmission shaft 8 to drive the output shaft 34 to rotate through the bevel gear transmission assembly 33. The output shaft 34 further drives the rotating disk 36 to rotate, and the connecting shaft 42 extends and retracts inside the rotating disk 36 as the rotating disk 36 rotates. This controls the connecting seat 39, which drives the sweeping plate 40 to repeatedly rotate around the flipping shaft 38, thereby sweeping the dust, stones, etc. on the road surface along the device's running path and avoiding interference with the normal detection and marking of the device.

[0027] A transmission belt assembly 9 is connected to the outer surface of the transmission shaft 8, located outside the detection device 1. A rotating shaft 10 is connected to the other end of the transmission belt assembly 9. A bevel gear transmission assembly 11 is connected to the other end of the rotating shaft 10. A stirring shaft 13 is connected to the lower end of the bevel gear transmission assembly 11, located inside the labeling liquid storage tank 12. After the dual-output shaft drive motor 7 is started, the transmission shaft 8 drives the rotating shaft 10 to rotate through the transmission belt assembly 9. Then, through the bevel gear transmission assembly 11, the stirring shaft 13 stirs the labeling liquid inside the labeling liquid storage tank 12, preventing the labeling liquid from solidifying due to prolonged static conditions, which would affect the normal detection and labeling process.

[0028] An infrared positioning and recording device 32 is installed inside the detection device 1 and at the front end of the moving rod 29. The infrared positioning and recording device 32 emits infrared rays to illuminate the surface of the moving rod 29. As the moving rod 29 moves, the position of the mark changes, thereby detecting the height, depth and length of the uneven road surface section.

[0029] A spring is provided at the top of the limiting cylinder 28 and on the outer surface of the moving rod 29. When the device moves, the contact wheel 30 is released from contact with the ground, causing the moving rod 29 to move rapidly downward. The spring cushions the movement of the moving rod 29, thereby improving the service life of the device.

[0030] The working principle of this road surface detection device is as follows: The device is powered by electric drive wheels 4 with buffer devices 3 at the bottom of the mounting frames 2 on both sides, which, together with the steering power wheel assembly 5 at the bottom front, enable movement and steering. The buffer device 3 can alleviate road vibration to ensure the stable operation of the detection mechanism. The cleaning unit of the detection mechanism first pushes away larger objects on the road surface through the front blocking cover 6. At the same time, after the dual output shaft drive motor 7 starts, its transmission shaft 8 drives the output shaft 34 and the rotating disk 36 to rotate through the bevel gear transmission assembly 2 33. The rotating disk 36 drives the connecting seat 39 through the connecting shaft 42 to drive the cleaning plate 40 to repeatedly rotate around the flip shaft 38, cleaning up small particles and stones on the road surface to avoid interfering with detection and marking. The transmission shaft 8 also drives the stirring shaft 13 to rotate through the transmission belt assembly 9, the rotating shaft 10 and the bevel gear transmission assembly 11 to stir the marking liquid in the marking liquid storage tank 12 to prevent solidification. During detection, the rotating rod on the flip L bracket 15 is rotated. 17. The baffle 19 inside the slide rail 20 is moved by the traction rod 18, so that the discharge port 21 of the baffle 19 is aligned with the transfer pipe. The marking liquid is collected by the guide slope 22 inside the transfer box 14 and flows into the discharge pipe 23. During the movement of the device, the contact wheel 30 contacts the ground. When the road surface is uneven or has potholes, the moving rod 29 moves up and down inside the limiting cylinder 28 (the spring at the top of the limiting cylinder 28 acts as a buffer). The moving rod 29 pulls the connecting rod 27 through the connecting plate 31, so that the sealing plate 25 moves in the moving groove 26 of the supporting housing 24 to open the discharge pipe 23. The moving height of the moving rod 29 controls the opening range of the sealing plate 25, thereby adjusting the width of the marking liquid release. At the same time, the infrared positioning and recording device 32 in the detection device 1 records the height, depth and length of the uneven road section by irradiating the surface of the moving rod 29 according to its position change, so as to realize the detection, marking and recording of road defects for subsequent maintenance by the staff.

[0031] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0032] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A road surface quality testing device for highway traffic engineering, comprising a testing device (1) and a mounting frame (2), characterized in that: The mounting bracket (2) is installed on the side of the detection device (1). The detection device (1) is equipped with a detection mechanism inside. The detection mechanism includes a marking unit and a cleaning unit. The marking unit is installed inside the detection device (1), and the cleaning unit is installed at the front end of the detection device (1). The marking unit includes a marking liquid storage tank (12), which is installed above the detection device (1). An L-bracket (15) is fixedly connected to the top of the detection device (1). The L-bracket (15) is provided with a central shaft (16). A rotating rod (17) is movably connected to the outer surface of the central shaft (16). A traction rod (18) is connected to the other end of the rotating rod (17). A baffle (19) is connected to the other end of the traction rod (18). A slide rail (20) is provided on the top surface inside the detection device (1). A transfer box (14) is provided inside the detection device (1). A discharge pipe (23) is connected to the side of the transfer box (14). A support housing (24) is provided at the bottom of the detection device (1) and on the outer surface of the discharge pipe (23). A moving groove (26) is provided inside the support housing (24). A sealing plate (25) is movably connected inside the moving groove (26). A connecting rod (27) is fixedly connected to the side of the sealing plate (25). A limiting cylinder (28) is provided inside the detection device (1). A moving rod (29) is movably connected inside the limiting cylinder (28). A contact wheel (30) is provided at the bottom of the moving rod (29). A connecting plate (31) is connected to the center of the contact wheel (30) by a rotating shaft. The connecting plate (31) is connected to the connecting rod (27).

2. The road surface quality testing device for highway traffic engineering according to claim 1, characterized in that: The transfer box (14) is provided with a guide slope (22) inside.

3. The road surface quality testing device for highway traffic engineering according to claim 1, characterized in that: The baffle (19) moves inside the slide rail (20), and a discharge port (21) is provided inside the baffle (19).

4. The road surface quality testing device for highway traffic engineering according to claim 1, characterized in that: The detection device (1) is provided with mounting brackets (2) on both sides, and a buffer device (3) is provided at the bottom of the mounting brackets (2). An electric drive wheel (4) is connected to the other end of the buffer device (3). A steering power wheel assembly (5) is provided at the center of the bottom front end of the detection device (1).

5. A road surface quality testing device for highway traffic engineering according to claim 1, characterized in that: The cleaning unit includes a baffle (6), which is fixedly connected to the front end of the detection device (1). A dual-output shaft drive motor (7) is installed inside the detection device (1). The output shaft of the dual-output shaft drive motor (7) is connected to a drive shaft (8). A bevel gear transmission assembly two (33) is connected to the side of the drive shaft (8). An output shaft (34) is connected to the front of the bevel gear transmission assembly two (33). A fixed cylinder (35) is installed on the outer surface of the output shaft (34). The fixed cylinder (35) is fixedly connected to the inside of the detection device (1). The output shaft (34) is away from the bevel gear. One end of the wheel drive assembly (33) is fixedly connected to a rotating disk (36). The rotating disk (36) is movably connected to a connecting shaft (42). The outer surface of the fixed cylinder (35) is fixedly connected to a limiting rod (37). The inside of the limiting rod (37) is movably connected to a flipping shaft (38). The outer surface of the flipping shaft (38) is movably connected to a connecting seat (39). The side of the connecting seat (39) is fixedly connected to a cleaning plate (40). The inner side of the end of the connecting seat (39) away from the cleaning plate (40) is fixedly connected to a fixing rod (41). The connecting shaft (42) is located on the outer surface of the fixing rod (41).

6. A road surface quality testing device for highway traffic engineering according to claim 5, characterized in that: The outer surface of the drive shaft (8) and located outside the detection device (1) is connected to a drive belt assembly (9). The other end of the drive belt assembly (9) is connected to a rotating shaft (10). The other end of the rotating shaft (10) is connected to a bevel gear drive assembly (11). The lower end of the bevel gear drive assembly (11) and located inside the labeling liquid storage tank (12) is connected to a stirring shaft (13).

7. A road surface quality testing device for highway traffic engineering according to claim 1, characterized in that: An infrared positioning and recording device (32) is provided inside the detection device (1) and at the front end of the moving rod (29).

8. A road surface quality testing device for highway traffic engineering according to claim 1, characterized in that: A spring is provided on the top of the limiting cylinder (28) and on the outer surface of the moving rod (29).

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