Novel bridge prestressed pipeline inspection device
By designing a bridge prestressed duct inspection device, which employs a retractable ruler and laser detection technology, the problem of prestressed duct installation position deviation was solved, enabling precise detection and fixation, and improving the safety and load-bearing capacity of the bridge.
Patent Information
- Application Number
- CN202520399688.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-07
- Publication Date
- 2025-12-26
- Estimated Expiration
- 2035-03-07
AI Technical Summary
In bridge construction, it is difficult to accurately check the installation position deviation of prestressed ducts, which affects the load-bearing capacity and safety of the bridge. This is especially true in box girders or continuous beams, where the dense reinforcement makes inspection difficult.
Design a bridge prestressed duct inspection device, including a telescopic ruler and adjustment components, equipped with a laser emitting device, which detects the position of the prestressed duct by means of a laser beam, and uses telescopic and fastening components to ensure that the device is fixed to the bridge web, so as to achieve accurate detection.
It improved the accuracy of prestressed duct installation, reduced reference plane offset error, simplified the inspection process, and ensured the safety and load-bearing capacity of the bridge.
Smart Images
Figure CN223727011U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application relates to the field of bridge construction equipment, in particular to a novel bridge prestressed pipe inspection device. BACKGROUND
[0002] As an important infrastructure of modern transportation, the safety and stability of a bridge are of great concern. In the long-term use process, the bridge will bear various stresses due to various loads, natural environment and other factors, which will cause the deformation of the bridge structure and even cause serious problems such as cracks and fractures, thereby seriously affecting the safety, carrying capacity and service life of the bridge.
[0003] In order to improve the safety, carrying capacity and service life of the bridge, prestressed technology is often used in the design of the bridge. The prestressed technology can effectively reduce the stress damage degree of the road bridge, maximize the improvement of the bridge foundation performance, save the engineering construction raw materials, reduce the cost and improve the economic benefit of the construction enterprise. The prestressed technology can improve the rigidity and stability of the bridge by applying a pre-pressure to the bridge, reduce the stress and deformation of the bridge deck and thereby improve the carrying capacity and service life of the road bridge. Meanwhile, the prestressed technology can also improve the crack resistance and durability of the road bridge and enhance the adaptability of the bridge to the environmental conditions.
[0004] Therefore, in the bridge construction process, the positioning accuracy of the prestressed pipe is very important. When the position deviation of the prestressed pipe exceeds the specification requirement, the carrying capacity of the whole bridge will be affected. In order to fully play the role of the prestress, it is necessary to inspect the installation position of the prestressed pipe during the construction process. However, in the installation process of the prestressed pipe of the box girder or continuous girder, the position deviation of the prestressed pipe often exceeds the specification requirement due to the dense steel bars and the technical level of the construction personnel. It is difficult to inspect the position of all the prestressed pipes due to the dense steel bars and prestressed pipes in the bottom web of the box girder or continuous girder. CONTENT OF THE INVENTION
[0005] In order to facilitate the inspection of the installed prestressed pipe position by the supervisors and assist in positioning during the installation of the prestressed pipe and improve the accuracy of the installation position of the prestressed pipe, the application provides a novel bridge prestressed pipe inspection device.
[0006] The novel bridge prestressed pipe inspection device provided by the application adopts the following technical scheme:
[0007] A novel bridge prestressed pipe inspection device comprises:
[0008] The ruler body comprises a main ruler and two extension rulers connected to the ruler body along the length direction of the ruler body, the main ruler and the extension rulers are both provided with a plurality of laser emitting devices along the length direction of the main ruler and the extension rulers; and the ruler body further comprises:
[0009] An adjusting assembly is arranged between the main ruler and the extension rulers, and is used for adjusting and locking the total length of the main ruler and the extension rulers; and a fastening assembly is arranged at the end of the extension ruler away from the main ruler, and is used for fixing the ruler body.
[0010] By using the above technical scheme, when the position of the prestressed pipe in the box girder or the continuous girder is detected by the prestressed pipe inspection device, first, the supervisor erects the telescopic ruler body between the webs of the box girder or the continuous girder, and then expands the main ruler and the extension rulers by the telescopic part in the adjusting assembly until the fastening assemblies at the ends of the extension rulers on both sides are in close contact with the surface of the web and are locked, at this time, the laser beams projected by the laser emitting devices distributed along the length direction of the ruler body are parallel, then the supervisor observes the relative position between the surface of the prestressed pipe and the laser spot by means of the tape measure, when the deviation between the actual axis of the prestressed pipe and the laser beam exceeds the allowable tolerance range, it indicates that the installation position of the prestressed pipe is unqualified, and subsequent adjustment measures need to be taken; wherein the ruler body is telescopic to adapt to box girders or continuous girders of different widths, the fastening assemblies on both sides of the ruler body facilitate the quick fixing of the prestressed pipe inspection device between the webs on both sides, so as to detect the installation deviation of the prestressed pipe and improve the accuracy of the installation position of the prestressed pipe.
[0011] Optionally, the telescopic part comprises:
[0012] A rotating shaft is rotatably connected to the main ruler;
[0013] A drive gear is fixedly sleeved outside the rotating shaft, two parallel racks are respectively engaged with the two sides of the drive gear, and the two racks are in one-to-one correspondence with and fixedly connected to the two extension rulers;
[0014] A ratchet wheel is fixedly sleeved outside the rotating shaft;
[0015] A pawl is rotatably connected to the main ruler, the pawl is engaged with the ratchet wheel, and a torsional spring is further arranged between the pawl and the main ruler, the torsional spring gives the pawl a force close to the ratchet wheel;
[0016] A pull rod is hingedly connected to one end of the pawl and located outside the main ruler at the other end.
[0017] When the supervisor pulls the extension ruler outward, the rack connected with the extension ruler generates linear displacement, drives the driving gear meshed with the rack to rotate around the rotating shaft, and drives the two extension rulers to expand synchronously at equal distances when the driving gear rotates. The rotating shaft drives the ratchet wheel to rotate synchronously. When the extension ruler expands outward, the tooth groove of the ratchet wheel is in one-way meshing state with the pawl, and the pawl is clamped into the tooth groove of the ratchet wheel to form mechanical self-locking when there is no external force intervention, thereby preventing the rotating shaft from rotating reversely and fixing the total length of the ruler body. When the ruler body needs to be retracted, the supervisor pulls the pull rod outward, the pull rod drives the pawl to rotate around the fulcrum, and the pawl is separated from the tooth groove of the ratchet wheel by overcoming the pre-tightening force of the torsional spring. At this time, the rotating shaft is unlocked, and the extension ruler can drive the rack to retract into the main ruler. Because the two racks are parallel and symmetrically arranged, the driving gear drives the two extension rulers to expand synchronously at equal distances when the driving gear rotates, so that the extension lengths of the two sides of the ruler body can always remain consistent, thereby reducing the error of the reference surface caused by unilateral adjustment. The total length of the ruler body can be locked in one direction by the self-locking structure of the ratchet wheel and the pawl, so that the position of the bridge prestressed pipe inspection device can be fixed.
[0018] Optionally, a coil spring is further arranged between the rotating shaft and the main ruler.
[0019] By adopting the above technical scheme, as the extension stroke of the extension ruler increases, the coil spring continuously accumulates elastic potential energy. When the supervisor pulls the pull rod to unlock the ratchet wheel, the elastic potential energy accumulated in the coil spring drives the rotating shaft to rotate reversely. The reverse rotation is converted into synchronous retraction of the extension ruler through the driving gear and the rack, so that the ruler body can be automatically rebounded and stored.
[0020] Optionally, the fastening component comprises:
[0021] A fastening screw is threadedly connected to the end of the extension ruler and is arranged along the length direction of the extension ruler.
[0022] A driven bevel gear is slidably sleeved outside the fastening screw.
[0023] A rotating shaft is rotationally connected to the end of the extension ruler, and a driving bevel gear is fixedly sleeved outside the rotating shaft. The driving bevel gear is meshed with the driven bevel gear.
[0024] A pressing plate is rotationally connected to the end of the fastening screw away from the extension ruler.
[0025] By adopting the above technical scheme, when the rotating shaft rotates, the driving bevel gear fixed to the end of the shaft begins to rotate, then the driving bevel gear drives the driven bevel gear and the fastening screw to rotate, and the fastening screw generates axial displacement in the threaded hole at the end of the extension ruler. When the fastening screw extends outward, the pressing plate contacts the surface of the web plate and abuts tightly, so that the ruler body can be fixed.
[0026] Optionally, a rubber pad is arranged on the end of the pressing plate away from the fastening screw.
[0027] By using the above technical scheme, when the pressing plate approaches the bridge web, the rubber pad preferentially contacts the concrete surface, and the rubber material is easy to elastically deform, automatically fills the fine cracks or uneven areas on the surface, and forms a continuous contact interface, so that the ruler body is not easy to slide down after being fixed.
[0028] Optionally, the main ruler and the extension ruler are both provided with a sliding groove along the length direction thereof, a plurality of sliding blocks are slidably connected in the sliding groove, the plurality of sliding blocks correspond to the plurality of laser emitting devices one by one, a connecting rod is fixedly arranged below the sliding block, and the bottom of the connecting rod is connected with the laser emitting device.
[0029] By using the above technical scheme, the number of laser emitting devices can be flexibly increased according to actual conditions, and the sliding block is inserted into the sliding groove and moved to the position to be detected when the laser emitting device is increased.
[0030] Optionally, a locking seat is slidably sleeved on the outer side of the connecting rod, the locking seat abuts against the bottom of the main ruler or the bottom of the extension ruler, a spring is fixedly arranged between the locking seat and the sliding block, and the spring gives the locking seat an upward pulling force.
[0031] By using the above technical scheme, the spring continuously applies pressure to the locking seat, so that the locking seat tightly abuts against the bottom of the main ruler or the bottom of the extension ruler, thereby locking the position of the laser emitting device; when it is necessary to adjust the position of the laser emitting device, the connecting rod is pulled downward, so that the locking seat is separated from the bottom of the main ruler or the bottom of the extension ruler, and then the connecting rod is moved, so that the laser emitting device in the sliding groove is moved.
[0032] Optionally, the main ruler and the extension ruler are both provided with a scale.
[0033] By using the above technical scheme, the supervisor can accurately adjust the position of the laser emitting device through the scale, and the detection efficiency is improved.
[0034] In summary, the present application has at least one of the following beneficial technical effects:
[0035] 1. The ruler body is telescopic to adapt to different width box girders or continuous girders, the ruler body is provided with fastening components on both sides, the pre-stressed pipe inspection device is quickly fixed between the two side webs, so that the installation deviation of the pre-stressed pipe is detected, and the accuracy of the installation position of the pre-stressed pipe is improved.
[0036] 2. The two racks on both sides of the telescopic part are arranged in parallel and are centrally symmetrical, when the driving gear rotates, the two extension rulers are simultaneously driven to expand at equal distances, which can ensure that the extension lengths of the rulers on both sides remain consistent, thereby reducing the error of the reference surface caused by unilateral adjustment, and the total length of the ruler can be locked in one direction through the self-locking structure of the ratchet and pawl, which is convenient for fixing the position of the bridge prestressed pipe inspection device;
[0037] 3. As the extension ruler extends, the coil spring continuously accumulates elastic potential energy, when the supervisor pulls the pull rod to release the ratchet locking, the elastic potential energy accumulated by the coil spring drives the rotating shaft to rotate, and the rotation is converted into the synchronous contraction of the extension ruler through the driving gear and the rack, thereby achieving the automatic rebounding of the ruler;
[0038] 4. On the one hand, the number of laser emitting devices can be flexibly increased according to actual conditions, and on the other hand, the spring continuously applies pressure to the locking seat, so that the locking seat tightly abuts against the bottom of the main ruler or the bottom of the extension ruler, thereby locking the position of the laser emitting device; when it is necessary to adjust the position of the laser emitting device, the connecting rod is pulled downward to separate the locking seat from the bottom of the main ruler or the bottom of the extension ruler, and then the connecting rod is moved to drive the laser emitting device to move in the sliding groove. BRIEF DESCRIPTION OF DRAWINGS
[0039] Figure 1 is a structural schematic diagram of the bridge prestressed pipe inspection device in the present application;
[0040] Figure 2 is a partial structural schematic diagram of the bridge prestressed pipe inspection device;
[0041] Figure 3 is a partial sectional view of the telescopic part;
[0042] Figure 4 is a partial sectional view of the fastening part.
[0043] BRIEF DESCRIPTION OF DRAWINGS 1. ruler body; 11, main ruler; 12, extension ruler; 13, sliding groove; 2, adjustment assembly; 21, telescopic part; 211, rotating shaft; 212, driving gear; 213, rack; 214, ratchet; 215, pawl; 216, torsion spring; 217, pull rod; 218, coil spring; 22, fastening part; 221, fastening screw; 222, spline shaft; 223, driven bevel gear; 224, rotating shaft; 225, driving bevel gear; 226, pressing plate; 227, rubber pad; 3, laser emitting device; 4, sliding block; 5, connecting rod; 6, locking seat; 7, spring; 8, scale. DETAILED DESCRIPTION
[0044] The present application will be further described in detail below with reference to the accompanying drawings. Figures 1-4 The present application will be further described in detail below with reference to the accompanying drawings.
[0045] The embodiment of the present application discloses a novel bridge prestressed pipe inspection device. Figure 1 and Figure 2 The bridge prestressed pipe inspection device comprises a ruler body 1 and an adjusting assembly 2, the ruler body 1 comprises a main ruler 11 and two extension rulers 12 slidably connected to the ruler body 1, and the two extension rulers 12 are arranged along the length direction of the ruler body 1. A plurality of laser emitting devices 3 are arranged at intervals along the length direction of the main ruler 11 and the extension rulers 12. The adjusting assembly 2 comprises a telescopic component 21 arranged between the main ruler 11 and the extension rulers 12 and a fastening component 22 arranged at the end of the extension ruler 12 away from the main ruler 11, wherein the telescopic component 21 is used for adjusting and locking the total length of the main ruler 11 and the extension rulers 12, and the fastening component 22 is used for fixing the ruler body 1.
[0046] When the bridge prestressed pipe inspection device is used to detect the position of the prestressed pipe in the box girder or the continuous girder, first of all, the supervisor erects the telescopic ruler body 1 between the webs of the box girder or the continuous girder, expands the main ruler 11 and the extension rulers 12 through the telescopic component 21 in the adjusting assembly 2, and then locks the fastening components 22 at the ends of the two extension rulers 12 in close contact with the surface of the web. At this time, the laser emitting devices 3 arranged at intervals along the length direction of the ruler body 1 project parallel laser beams, and then the supervisor observes the relative position between the surface of the prestressed pipe and the laser spot by means of the tape measure. When the deviation between the actual axis of the prestressed pipe and the laser beam exceeds the allowable tolerance range, it indicates that the installation position of the prestressed pipe is unqualified, and subsequent adjustment measures need to be taken. The telescopic ruler body 1 can be telescoped to adapt to box girders or continuous girders of different widths, and the telescopic ruler body 1 is provided with the fastening components 22 on both sides, so that the bridge prestressed pipe inspection device can be quickly fixed between the two webs, thereby detecting the installation deviation of the prestressed pipe and improving the accuracy of the installation position of the prestressed pipe.
[0047] Referring to Figure 1 and Figure 2 The main ruler 11 and the extension rulers 12 are both provided with sliding grooves 13 along the length direction thereof, and a plurality of sliding blocks 4 are slidably connected in the sliding grooves 13. The plurality of sliding blocks 4 correspond to the plurality of laser emitting devices 3 one by one, a connecting rod 5 is fixedly arranged below the sliding block 4, and the bottom of the connecting rod 5 is connected with the laser emitting device 3. A locking seat 6 is also slidably arranged outside the connecting rod 5, and the locking seat 6 abuts against the bottom of the main ruler 11 or the extension ruler 12. A spring 7 is fixedly arranged between the locking seat 6 and the sliding block 4, and the spring 7 gives the locking seat 6 an upward pulling force. The main ruler 11 and the extension rulers 12 are both provided with scales 8, and the supervisor can accurately adjust the position of the laser emitting device 3 through the scales 8.
[0048] The number of laser emitting devices 3 can be flexibly increased according to actual conditions. When the laser emitting device 3 is increased, the slider 4 is inserted into the sliding groove 13, the spring 7 continuously applies pressure to the locking seat 6, so that the locking seat 6 is tightly attached to the bottom of the main ruler 11 or the bottom of the extension ruler 12, thereby locking the position of the laser emitting device 3. When it is necessary to adjust the position of the laser emitting device 3, the connecting rod 5 is pulled downward, so that the locking seat 6 is separated from the bottom of the main ruler 11 or the bottom of the extension ruler 12, and then the connecting rod 5 is moved, thereby moving the laser emitting device 3 in the sliding groove 13.
[0049] With reference to Figure 1 and Figure 3 The telescopic part 21 comprises a rotating shaft 211 rotatably connected to the main ruler 11, a drive gear 212 fixedly sleeved outside the rotating shaft 211, two parallel racks 213 meshing with the two sides of the drive gear 212 respectively, and two extension rulers 12 fixedly connected with the two racks 213 respectively. A ratchet wheel 214 is fixedly sleeved outside the rotating shaft 211, a pawl 215 is rotatably connected to the main ruler 11, and the pawl 215 is meshed with the ratchet wheel 214. A torsion spring 216 is arranged between the pawl 215 and the main ruler 11, and the torsion spring 216 gives the pawl 215 a force close to the ratchet wheel 214. One end of the pawl 215 is hingedly connected with a pull rod 217, and the other end of the pawl 215 is located outside the main ruler 11. A coil spring 218 is further arranged between the rotating shaft 211 and the main ruler 11.
[0050] When the supervisor pulls the extension ruler 12 outward, the rack 213 connected with the extension ruler 12 generates a linear displacement, drives the drive gear 212 meshing therewith to rotate around the rotating shaft 211, and drives the two extension rulers 12 to be expanded at equal distances and synchronously when the drive gear 212 rotates. The rotating shaft 211 simultaneously drives the ratchet wheel 214 to rotate, and when the extension ruler 12 is extended outward, the tooth groove of the ratchet wheel 214 and the pawl 215 form a one-way meshing state. When there is no external force intervention, the pawl 215 is clamped into the tooth groove of the ratchet wheel 214 to form mechanical self-locking, thereby preventing the rotating shaft 211 from rotating reversely, so as to fix the total length of the ruler body 1. With the increase of the extension stroke of the extension ruler 12, the coil spring 218 continuously accumulates elastic potential energy.
[0051] When the ruler body 1 needs to be retracted, the supervisor pulls the pull rod 217 outward, which drives the pawl 215 to rotate around the fulcrum, and the pawl 215 is disengaged from the tooth groove of the ratchet wheel 214 against the pre-tightening force of the torsional spring 216. At this time, the rotating shaft 211 is unlocked, and the elastic potential energy accumulated in the coil spring 218 drives the rotating shaft 211 to rotate, and the rotation is transmitted to the synchronous retraction of the extension ruler 12 through the driving gear 212 and the rack 213, realizing the automatic rebound storage of the ruler body 1. Since the two racks 213 are parallel and centrally symmetric, the driving gear 212 rotates to drive the two extension rulers 12 to realize equidistant synchronous expansion, which can ensure that the extension lengths of the two sides of the ruler body 1 remain consistent at all times, thereby reducing the reference surface deviation error caused by unilateral adjustment, and the self-locking structure of the ratchet wheel 214 and the pawl 215 can lock the total length of the ruler body 1 in one direction, facilitating the positioning of the bridge prestressed pipe inspection device.
[0052] With reference to Figure 4 The fastening component 22 comprises a fastening screw 221 threadedly connected to the end of the extension ruler 12, and the fastening screw 221 is arranged along the length direction of the extension ruler 12. A spline shaft 222 is fixedly arranged on the end of the fastening screw 221 close to the extension ruler 12, and a driven bevel gear 223 is slidably arranged on the outer side of the spline shaft 222. A rotating shaft 224 is rotatably connected to the end of the extension ruler 12, and a driving bevel gear 225 is fixedly arranged on the outer side of the rotating shaft 224, and the driving bevel gear 225 is in mesh with the driven bevel gear 223. A pressing plate 226 is rotatably connected to the end of the fastening screw 221 away from the extension ruler 12, and a rubber pad 227 is arranged on the end of the pressing plate 226 away from the fastening screw 221.
[0053] When the rotating shaft 224 rotates, the driving bevel gear 225 fixed to the shaft end begins to rotate, and then the driving bevel gear 225 drives the driven bevel gear 223 and the fastening screw 221 to rotate, and at the same time, the fastening screw 221 produces axial displacement in the threaded hole at the end of the extension ruler 12. When the fastening screw 221 extends outward, the pressing plate 226 moves towards the side close to the bridge web, and the rubber pad 227 preferentially contacts the concrete surface of the box girder or continuous girder web, thereby realizing the fixation of the ruler body 1. The rubber pad 227 is easy to elastically deform and automatically fill the fine cracks or uneven areas on the surface, thereby forming a continuous contact interface, so that the ruler body 1 is not easy to slide after being fixed.
[0054] The implementation principle of the novel bridge prestressed pipe inspection device is as follows: when the bridge prestressed pipe inspection device detects the position of the prestressed pipe in the box girder or continuous girder, first, the supervisor erects the telescopic ruler body 1 between the webs of the box girder or continuous girder, and expands the main ruler 11 and the extension ruler 12 in the telescopic component 21 of the adjusting assembly 2 until the fastening components 22 at the ends of the extension rulers 12 on both sides are in close contact with the surface of the web and are locked. At this time, the laser emitting devices 3 distributed along the length direction of the ruler body 1 will project parallel laser beams, and then the supervisor observes the relative position between the surface of the prestressed pipe and the laser spot by means of the tape measure. When the deviation between the actual axis of the prestressed pipe and the laser beam exceeds the allowable tolerance range, it indicates that the installation position of the prestressed pipe is unqualified, and subsequent adjustment measures need to be taken.
[0055] The above are preferred embodiments of the present application, and do not limit the protection scope of the present application, so that: any equivalent changes made according to the structure, shape, principle of the present application should be covered within the protection scope of the present application.
Claims
1. A new type of bridge prestressed duct inspection device, characterized in that, The utility model relates to a laser ruler, including: The ruler body (1) includes the main ruler (11) and two extension rulers (12) slidingly connected to the ruler body (1) along the length direction, the main ruler (11) and the extension ruler (12) are spaced apart and provided with a plurality of laser emitting devices (3) along the length direction of itself, further including: Adjusting assembly (2), the adjusting assembly (2) includes telescopic part (21) and fastening part (22), wherein the telescopic part (21) is arranged between the main ruler (11) and the extension ruler (12), is used for adjusting and locking the total length of the main ruler (11) and the extension ruler (12), and the fastening part (22) is arranged at the end of the extension ruler (12) away from the main ruler (11), is used for fixing the ruler body (1).
2. A novel bridge pre-stressed duct inspection device according to claim 1, characterized in that, The telescopic part (21) includes: Rotary shaft (211), rotationally connected to the main ruler (11); Driving gear (212), fixedly sleeved on the outside of the rotary shaft (211), the driving gear (212) is meshed with two mutually parallel racks (213) on both sides respectively, two racks (213) and two extension rulers (12) correspond one by one and are fixedly connected; Ratchet wheel (214), fixedly sleeved on the outside of the rotary shaft (211); Pawl (215), rotationally connected to the main ruler (11), the pawl (215) is meshed with the ratchet wheel (214), and a torsional spring (216) is further arranged between the pawl (215) and the main ruler (11), the torsional spring (216) gives the pawl (215) a force close to the ratchet wheel (214); Pull rod (217), one end is hinged to the pawl (215), the other end is located on the outside of the main ruler (11).
3. A novel bridge pre-stressed duct inspection device according to claim 2, characterized in that, The rotary shaft (211) and the main ruler (11) are further provided with a coil spring (218).
4. A new type of bridge prestressed pipe inspection device according to claim 1, characterized in that, The fastening part (22) includes: Fastening screw (221), threadedly connected to the end of the extension ruler (12), and arranged along the length direction of the extension ruler (12); Driven bevel gear (223), slidingly sleeved on the outside of the fastening screw (221); Rotary shaft (224), rotationally connected to the end of the extension ruler (12), and the outside of the rotary shaft (224) is fixedly sleeved with driving bevel gear (225), the driving bevel gear (225) and the driven bevel gear (223) are meshed with each other; Pressing plate (226), rotationally connected to the end of the fastening screw (221) away from the extension ruler (12).
5. A novel bridge pre-stressed duct inspection device according to claim 4, characterized in that, The end of the pressing plate (226) away from the fastening screw (221) is paved with rubber pad (227).
6. A new type of bridge pre-stressed duct inspection device according to any one of claims 1-5, characterized in that, The main ruler (11) and the extension ruler (12) are both provided with a sliding groove (13) along the length direction of itself, a plurality of sliding blocks (4) are slidingly connected in the sliding groove (13), a plurality of sliding blocks (4) correspond to a plurality of laser emitting devices (3) one by one, a connecting rod (5) is fixedly arranged below the sliding block (4), and the bottom of the connecting rod (5) is connected with the laser emitting device (3).
7. A novel bridge pre-stressed duct inspection device as claimed in claim 6, wherein, The connecting rod (5) is sleeved with a locking seat (6) on the outside, which abuts against the bottom of the main ruler (11) or the bottom of the extension ruler (12), and a spring (7) is fixed between the locking seat (6) and the sliding block (4), which gives the locking seat (6) an upward pulling force.
8. A novel bridge pre-stressed duct inspection device as claimed in claim 6, wherein, The main ruler (11) and the extension ruler (12) are both provided with scales (8).