Safety device for trench excavation

Abstract

The application discloses a safety protection device for trench excavation, which comprises a support plate body, a fixing shell, a push rod, a linkage rod and a transmission mechanism; a pair of support plate bodies are oppositely arranged, and a plurality of fixing shells are vertically and intervally arranged between the pair of support plate bodies; each fixing shell is movably connected with the pair of support plate bodies through the transmission mechanism and the push rod, a plurality of groups of transmission mechanisms are connected in linkage through the linkage rod, and the pair of push rods form an inverted V-shaped structure or a linear structure between the fixing shell and the pair of support plate bodies, so that the pair of support plate bodies can be supported on the sidewalls of the trench. The application relates to the technical field of building construction and can solve the problems of high cost, large occupied storage space and low dismounting and replacing efficiency of the trench support structure in the prior art.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of building construction, and in particular to a safety protection device for trench excavation. BACKGROUND

[0002] The drainage pipe network of a city is an important part of city infrastructure, and in the prior art, trench excavation is required before pipe construction, and then the pipe is placed in the trench for splicing and assembly, and then backfilling is performed to complete the pipe laying. After the trench is excavated, a supporting structure needs to be set up in it to ensure that the soil on both sides does not collapse towards the middle, so as to ensure the safety of the construction.

[0003] The trench supporting structure of the prior art includes two supporting plates supported by a section steel between the two supporting plates, which can achieve good protection effect, but the section steel is of fixed length and cannot adapt to trenches of different widths. In the process of pipe laying of the city drainage pipe network, according to the drainage requirements and geological conditions, it is inevitable to have the butt joint laying of variable diameter pipes, and different widths of trenches may be encountered in one project, requiring different lengths of section steel for support, which has the problems of high cost, large storage space occupied by section steel of different sizes, and low efficiency of disassembly and replacement of section steel, reducing the construction efficiency and affecting the construction progress. Therefore, it is necessary to provide a safety protection device for trench excavation, which can solve the problems of high cost, large storage space occupation, and low efficiency of disassembly and replacement of the trench supporting structure in the prior art. SUMMARY

[0004] The present application relates to the technical field of building construction, and in particular to a safety protection device for trench excavation.

[0005] The present application is implemented as follows:

[0006] A safety protection device for trench excavation includes a support plate body, a fixed shell, a push rod, a linkage rod, and a transmission mechanism. A pair of support plate bodies are arranged opposite to each other, and a plurality of fixed shells are vertically spaced apart between the pair of support plate bodies. Each fixed shell is movably connected to the pair of support plate bodies through the transmission mechanism via the push rod, and a plurality of groups of transmission mechanisms are connected in linkage through the linkage rod. The pair of push rods form an inverted V-shaped structure or a straight line structure between the fixed shell and the pair of support plate bodies, so that the pair of support plate bodies can be supported on the two side walls of the trench.

[0007] Each of the transmission mechanisms comprises a first rotating rod, a U-shaped block, a second rotating rod and a worm gear; a plurality of worm sections are formed on the linkage rod at intervals, and the worm sections are located in a plurality of fixed shells respectively; a pair of worm gears are rotatably installed in the fixed shells through the first rotating rods, and the worm gears are meshingly connected on both sides of the worm sections of the linkage rod; the closed ends of a pair of U-shaped blocks are fixedly installed on the inner walls of a pair of support plate bodies respectively, a pair of second rotating rods are rotatably installed in the open ends of the U-shaped blocks respectively, and a pair of push rods are connected between the first rotating rods and the second rotating rods respectively and located on both sides of the worm sections.

[0008] The bottom of the linkage rod is provided with a rotating wheel, the bottom of the lowermost fixed shell is provided with a limiting rod, a limiting hole is formed on the rotating wheel, the limiting rod vertically penetrates the rotating wheel through the limiting hole, and the rotating wheel is locked below the lowermost fixed shell.

[0009] The top of the rotating wheel is connected with a connecting rod, the top of the connecting rod is provided with a square block, a square cavity with a matching cross section is formed in the bottom of the linkage rod, the square block is slidably inserted into the square cavity, and the rotating wheel is inserted with the limiting rod through the limiting hole or is separated from the limiting rod.

[0010] A spring is arranged in the square cavity, the upper end of the spring is fixedly connected with the bottom of the square block, and the lower end of the spring is fixedly connected with the bottom surface of the square cavity.

[0011] The support plate body comprises a support plate, a movable plate and a lifting mechanism; the lower part of the movable plate is slidably inserted into the upper cavity of the support plate through the lifting mechanism, the bottom of the support plate forms a wedge surface which is wide at the top and narrow at the bottom, and the top of the movable plate is provided with an eye ring; the U-shaped block is installed on the inner wall of the support plate.

[0012] The lifting mechanism comprises a threaded rod, a transmission rod, a second bevel gear, a first bevel gear and a knob; the lower part of the movable plate is formed with a screw hole matched with the threaded rod, the upper end of the threaded rod is matched and screwed in the movable plate, and the lower end of the threaded rod is rotatably installed in the cavity of the support plate; one end of the transmission rod is rotatably installed on the support plate through the knob, the other end of the transmission rod extends into the cavity and is coaxially fixedly connected with the second bevel gear, and the first bevel gear is coaxially fixedly connected with the threaded rod and is meshingly connected with the second bevel gear.

[0013] A hand wheel groove is formed on the outer wall of the support plate, and the knob is hiddenly installed in the hand wheel groove.

[0014] Compared with the prior art, the present application has the following beneficial effects:

[0015] 1、The present application is provided with a push rod, a linkage rod and a transmission mechanism, under the transmission of the linkage rod, a pair of push rods are driven to rotate through the transmission mechanism, so that a pair of push rods with inverted V-shaped structure drive a pair of support plate bodies to approach or move away from each other, which can adapt to different width grooves, without configuring different length steel profiles, solving the problems of high cost, large storage and transportation space caused by large number of steel profiles, and without disassembling the steel profile during use, solving the problem of low efficiency of disassembly and replacement, which is helpful to improve the construction efficiency and ensure the construction progress.

[0016] 2、The present application is provided with a linkage rod and a rotating wheel, the rotating wheel drives the linkage rod to rotate, the linkage rod drives each group of transmission mechanisms to move synchronously through each worm segment, and each pair of push rods rotates synchronously, so that the spacing adjustment of a pair of support plate bodies is more convenient and efficient, and the reliable locking of the spacing of a pair of support plate bodies is ensured through the insertion limiting between the limiting rod and the rotating wheel, thereby ensuring the supporting and protecting effect of the whole device in the groove.

[0017] 3、The present application is provided with a support plate body, which can be controlled by a knob to lift the movable plate relative to the support plate, so as to adapt to the requirements of different protection depths in grooves with different depths, and has good adaptability to grooves of various sizes, simple structure, convenient operation and low cost. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 is the front view of the safety protection device for trench excavation of the present application;

[0019] Figure 2 is the sectional view of the safety protection device for trench excavation of the present application;

[0020] Figure 3 is Figure 2 the enlarged view of A in FIG.

[0021] Figure 4 is Figure 2 the enlarged view of B in FIG.

[0022] In the figure, 1 is a support plate, 2 is a fixed shell, 3 is a first rotating rod, 4 is a U-shaped block, 5 is a push rod, 6 is a second rotating rod, 7 is a movable plate, 8 is a lifting ring, 9 is a threaded rod, 10 is a worm wheel, 11 is a linkage rod, 12 is a rotating wheel, 13 is a limiting rod, 14 is a transmission rod, 15 is a second bevel gear, 16 is a first bevel gear, 17 is a square block, 18 is a connecting rod, 19 is a spring, and 20 is a knob. DETAILED DESCRIPTION

[0023] The present application will be further described below in combination with the drawings and specific embodiments.

[0024] Please refer to the drawings Figure 1 and the drawings Figure 2The utility model provides a safety protection device for trench excavation, including support plate body, fixed shell 2, push rod 5, linkage rod 11 and transmission mechanism, a pair of support plate body is opposite and is arranged, and a plurality of fixed shell 2 is vertically spaced apart between a pair of support plate body, and each fixed shell 2 is movably connected with a pair of support plate body through transmission mechanism through push rod 5, and a plurality of transmission mechanisms are linked through linkage rod 11, and a pair of push rod 5 forms inverted V structure or a straight line structure between fixed shell 2 and a pair of support plate body, so that a pair of support plate body can be supported on the two side walls of the trench.

[0025] Under the transmission of linkage rod 11, a plurality of transmission mechanisms are synchronously linked and moved through linkage rod 11. Each transmission mechanism drives a pair of push rod 5 to rotate, so that a pair of push rod 5 forms inverted V structure (or V structure), which is used for adjusting the distance between a pair of support plate body, so that it can be supported on the two side walls of the trench, and the trench support effect can be ensured while adapting to trenches of different widths. When a pair of push rod 5 rotates to a horizontal state, i.e. a pair of push rod 5 rotates to form a straight line structure, the distance between a pair of support plate body is maximum. The length of push rod 5 can be adaptively selected according to the excavation width range of the trench, so that the distance between a pair of support plate body controlled by a pair of push rod 5 can meet the construction requirements.

[0026] Preferably, linkage rod 11 and a plurality of fixed shell 2 are installed on the upper part of support plate body, so as to leave pipeline laying space below linkage rod 11 and a plurality of fixed shell 2. However, in order to make the structure of the whole device more clear, the vertical space of a plurality of fixed shell 2 arranged in the drawings is larger. In actual structure, a plurality of fixed shell 2 can be arranged concentratedly on the upper part of support plate body to avoid interference with pipeline laying. Linkage rod 11 and a plurality of fixed shell 2 are arranged on both ends of support plate body along the length direction of the trench, so as to ensure that a pair of support plate body is uniformly stressed and protected stably.

[0027] Fixed shell 2 and transmission mechanism are arranged in groups, and the number of groups can be adaptively adjusted according to the support height and support strength requirements. Preferably, it is 2 groups, which can minimize the vertical arrangement height requirement while ensuring the support effect.

[0028] Push rod 5 can be made of steel components of Q235B and the like, which has high structural strength, so as to ensure that it will not be bent and deformed during use, and the support protection effect is ensured.

[0029] Please refer to the accompanying drawings Figure 2Each of the transmission mechanisms comprises a first rotating rod 3, a U-shaped block 4, a second rotating rod 6 and a worm wheel 10; a plurality of worm sections are formed on the linkage rod 11 in intervals, and the worm sections are located in the plurality of fixed shells 2 respectively; a pair of worm wheels 10 are rotatably installed in the fixed shells 2 through the first rotating rods 3, and the worm wheels 10 are meshingly and transmissionally connected on both sides of the worm sections of the linkage rod 11 respectively; the closed ends of a pair of U-shaped blocks 4 are fixedly installed on the inner walls of the pair of support plate bodies respectively, a pair of second rotating rods 6 are rotatably installed in the open ends of the pair of U-shaped blocks 4 through bearings respectively, and a pair of push rods 5 are connected between the pair of first rotating rods 3 and the pair of second rotating rods 6 and located on both sides of the worm sections.

[0030] When the linkage rod 11 rotates, the plurality of worm sections rotate synchronously, thereby meshingly and transmissionally driving the pair of worm wheels 10 on both sides. The worm wheels 10 drive the first rotating rods 3 to rotate at the same time, the first rotating rods 3 drive one end of the push rod 5 to rotate synchronously, the other end of the push rod 5 rotates around the second rotating rod 6, thereby driving the support plate body to move towards the linkage rod 11 or away from the linkage rod 11 while the push rod 5 rotates, the push rods 5 on both sides rotate synchronously, the included angle of the V-shaped structure decreases or increases, and the adaptive adjustment of the spacing between the pair of support plate bodies and the width of the groove is realized.

[0031] The plurality of transmission mechanisms synchronously and linkage-movably adjust the spacing between the pair of support plate bodies and the width of the groove, and the relative type steel replacement mode is adopted, so that the adjusting efficiency of the present application is high and the operation is convenient.

[0032] Please refer to the accompanying drawings Figure 2 The bottom of the linkage rod 11 is provided with a rotating wheel 12, the bottom of the lowermost fixed shell 2 is provided with a limiting rod 13, the limiting hole is formed on the rotating wheel 12, the limiting rod 13 vertically penetrates the rotating wheel 12 through the limiting hole, and the rotating wheel 12 is locked below the lowermost fixed shell 2.

[0033] Preferably, two limiting holes are formed on the two side portions of the rotating wheel 12 respectively, two limiting rods 13 are correspondingly arranged on the bottom of the fixed shell 2, the two limiting rods 13 and the two limiting holes are inserted to realize the reliable limiting locking of the rotating wheel 12, thereby locking the spacing between the pair of support plate bodies, and the supporting effect is ensured.

[0034] According to the actual use requirement, the rotating wheel 12 can also be arranged on the top of the linkage rod 11, the installation mode and the movement process are the same as those of the installation on the bottom of the linkage rod 11, and only the installation direction is different, which will not be described herein again.

[0035] Please refer to the accompanying drawings Figure 4The top of the rotating wheel 12 is connected with a connecting rod 18, the top of the connecting rod 18 is provided with a square block 17, the bottom of the linkage rod 11 is formed with a square cavity matching the square block 17, the square block 17 is slidably inserted into the square cavity, and the rotating wheel 12 is inserted with the limiting rod 13 through the limiting hole or separated from the limiting rod 13.

[0036] The construction personnel pull down the rotating wheel 12, the square block 17 is synchronously moved downward in the square cavity of the linkage rod 11 through the connecting rod 18, the rotating wheel 12 can be moved downward to separate from the limiting rod 13, the locking of the rotating wheel 12 by the limiting rod 13 is released, and then the rotating wheel 12 can be rotated.

[0037] The construction personnel push up the rotating wheel 12, the square block 17 is synchronously moved upward in the square cavity of the linkage rod 11 through the connecting rod 18, the rotating wheel 12 can be moved upward to make the limiting rod 13 penetrate through the limiting hole of the rotating wheel 12, and the rotating wheel 12 is locked.

[0038] Please refer to the accompanying drawings Figure 4 The square cavity is provided with a spring 19, the upper end of the spring 19 is fixedly connected with the bottom of the square block 17, and the lower end of the spring 19 is fixedly connected with the bottom surface of the square cavity.

[0039] Preferably, the spring 19 is in a slightly stretched state after installation, the locking reliability of the limiting rod 13 penetrating through the limiting hole of the rotating wheel 12 is ensured by the elastic force of the spring 19, and the rotating wheel 12 cannot fall. When the rotating wheel 12 is pulled down, the spring 19 is further stretched, so that the elastic force of the spring 19 can assist the resetting of the rotating wheel 12.

[0040] Please refer to the accompanying drawings Figure 1 and the accompanying drawings Figure 2 The support plate body comprises a support plate 1, a movable plate 7 and a lifting mechanism; the lower part of the movable plate 7 is inserted into the upper cavity of the support plate 1 in a lifting manner through the lifting mechanism, the bottom of the support plate 1 is formed with a wedge-shaped surface which is wide at the top and narrow at the bottom, the top of the movable plate 7 is provided with a lifting ring 8, and a U-shaped block 4 is installed on the inner wall of the support plate 1.

[0041] The support plate 1 can be a rectangular plate, the length of the support plate 1 is consistent with the length of the groove segment excavated each time, and the effective support of the excavated groove segment is facilitated. The movable plate 7 is inserted into the support plate 1 in a lifting manner, and is used for adjusting the height of the support plate body, so as to adapt to the protection requirements of grooves with different depths.

[0042] The lifting ring 8 is welded on the top of the movable plate 7, which is convenient for connecting the lifting equipment, and the lifting equipment can drag the whole device to move in the trench along with the trench excavation and pipeline laying progress.

[0043] Preferably, the support plate 1 and the movable plate 7 are coated with anticorrosive coating, so that the whole device has good corrosion resistance.

[0044] Please refer to the accompanying drawings Figure 3 The lifting mechanism comprises a threaded rod 9, a transmission rod 14, a second bevel gear 15, a first bevel gear 16 and a knob 20; the lower part of the movable plate 7 is formed with a screw hole matched with the threaded rod 9, so that the upper end of the threaded rod 9 is matched and screwed in the movable plate 7, and the lower end of the threaded rod 9 is rotatably installed in the cavity of the support plate 1 through a bearing; one end of the transmission rod 14 is rotatably installed on the support plate 1 through the knob 20, and the other end of the transmission rod 14 extends into the cavity and is coaxially fixedly connected with the second bevel gear 15; the first bevel gear 16 is coaxially fixedly connected with the threaded rod 9 and is in meshing transmission connection with the second bevel gear 15.

[0045] When the knob 20 rotates, the transmission rod 14 is driven to rotate synchronously, the second bevel gear 15 is driven to rotate synchronously by the transmission rod 14, the first bevel gear 16 is driven to rotate by the meshing transmission of the second bevel gear 15, and the threaded rod 9 is driven to rotate synchronously. Preferably, the second bevel gear 15 and the first bevel gear 16 can adopt 45° bevel gears.

[0046] Since the movable plate 7 can only move up and down in the cavity of the support plate 1, the rotation of the threaded rod 9 is converted into the linear motion of the movable plate 7 along the axis of the threaded rod 9 under the transmission of the thread, so that the lifting height of the movable plate 7 is controlled by the different rotation directions and rotation numbers of the knob 20, so as to adapt to trenches of different depths and ensure the supporting and protecting effect.

[0047] Please refer to the accompanying drawings Figure 3 The outer wall of the support plate 1 is formed with a hand wheel groove, and the knob 20 is hiddenly installed in the hand wheel groove.

[0048] Through the setting of the hand wheel groove, the knob 20 is embedded and hiddenly installed, which is also convenient for the manual rotation operation of the knob 20, and the knob 20 will not be extruded and rubbed with the wall and soil of the trench. In order to avoid the filling of soil into the hand wheel groove, a sealing plate can be rotatably arranged on the hand wheel groove through a hinge, and the hand wheel groove is closed when the knob 20 is not used, so as to protect the knob 20.

[0049] Please refer to the accompanying drawings Figure 1 to Figure 4 The use method of the trench excavation device in the trench excavation construction process and the working principle are as follows:

[0050] According to the depth of the trench excavation, the knob 20 is turned, and the knob 20 drives the transmission rod 14 to rotate synchronously. The transmission rod 14 drives the second bevel gear 15 to rotate synchronously. When the second bevel gear 15 rotates, it engages and transmits the first bevel gear 16. The first bevel gear 16 drives the threaded rod 9 to rotate synchronously.

[0051] The rotation of the threaded rod 9 is converted into linear motion of the movable plate 7 along the axial direction of the threaded rod 9 by the threaded rod 9, so that the movable plate 7 can be controlled to move up or down by turning the knob 20 clockwise or counterclockwise. At the same time, the number of turns of the knob 20 controls the linear motion stroke of the movable plate 7, thereby adjusting the protective height of the support plate 1 and the movable plate 7 to meet the support requirements of trenches of different depths.

[0052] After the first trench section is excavated, the entire assembly is lowered into the first trench section via lifting ring 8 and a lifting device. Depending on the width of the trench, the wheel 12 is pulled downward to disengage the limiting rod 13, releasing the restraint on the wheel 12. At this point, spring 19 is stretched and loaded. Rotating the wheel 12, via connecting rod 18 and block 17, drives the linkage rod 11 in synchronous rotation. The worm gear segments on the linkage rod 11 rotate synchronously, engaging the worm gears 10 on either side.

[0053] The transmission mechanisms in several fixed shells 2 move synchronously through several worm gear segments. The movement process of several groups of transmission mechanisms is the same. Here, a group of transmission mechanisms is taken as an example for detailed description: the two worm gears 10 rotate while driving the first rotating rod 3 and the push rod 5 connected thereto to rotate, so that the pair of push rods 5 rotate relative to the pair of support plates 1 through the second rotating rod 6, so that the angle between the pair of push rods 5 increases or decreases, thereby adjusting the spacing between the pair of support plates 1 to adapt to different groove widths.

[0054] After adjustment is in place, the rotating wheel 12 is released, and the elastic force of the spring 19 is used to drive the rotating wheel 12 to move upward and reset, and the limiting rod 13 passes through the limiting hole on the rotating wheel 12 to limit the rotation of the rotating wheel 12. Several groups of transmission mechanisms are locked synchronously, thereby locking the distance between a pair of support plates 1.

[0055] Supported by a pair of support plates, the pipe is hoisted between them and docked with the previous pipe. Excavation continues with the next trench section, and the entire assembly is dragged into the next trench section using a lifting device via lifting rings 8. The pipe in the next trench section is then hoisted. As the pipeline is laid, soil is backfilled and compacted section by section, ensuring that it does not affect the pipeline hoisting.

[0056] Repeat the construction process of trench excavation, device dragging, pipeline hoisting, and backfilling until the pipeline is laid.

[0057] The above merely preferred embodiments of the present application are not intended to limit the scope of the application, thus, any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the scope of the present application.

Claims

1. A safety protection device for trench excavation, characterized by: The invention comprises a supporting plate body, a fixed shell (2), a push rod (5), a linkage rod (11) and a transmission mechanism; a pair of supporting plate bodies are arranged opposite to each other, and a plurality of fixed shells (2) are arranged vertically spaced apart between the pair of supporting plate bodies; each fixed shell (2) is movably connected to a pair of supporting plate bodies via a push rod (5) through a transmission mechanism, and a plurality of transmission mechanisms are linked and connected via a linkage rod (11); a pair of push rods (5) form an inverted V-shaped structure or a straight-line structure between the fixed shell (2) and the pair of supporting plate bodies, so that the pair of supporting plate bodies can be supported on the groove walls on both sides of the groove; Each group of the transmission mechanism comprises a first rotating rod (3), a U-shaped block (4), a second rotating rod (6) and a worm gear (10); a plurality of worm segments are formed at intervals on the linkage rod (11), and the plurality of worm segments are respectively located in a plurality of fixed shells (2); a pair of worm gears (10) are rotatably mounted in the fixed shell (2) through the first rotating rod (3), and the pair of worm gears (10) are respectively meshed and connected to the two sides of the worm segment of the linkage rod (11); the closed ends of the pair of U-shaped blocks (4) are respectively fixedly mounted on the inner walls of the pair of support plate bodies, the pair of second rotating rods (6) are respectively rotatably mounted in the open ends of the pair of U-shaped blocks (4), and the pair of push rods (5) are respectively connected between the pair of first rotating rods (3) and the pair of second rotating rods (6) and are located on both sides of the worm segment; A rotating wheel (12) is provided at the bottom of the linkage rod (11), a limiting rod (13) is provided at the bottom of the fixed shell (2) located at the bottom, a limiting hole is formed on the rotating wheel (12), and the limiting rod (13) vertically penetrates the rotating wheel (12) through the limiting hole, so that the rotating wheel (12) is locked below the fixed shell (2) located at the bottom; The top of the rotating wheel (12) is connected to a connecting rod (18), and a block (17) is provided on the top of the connecting rod (18). A square cavity with a cross section matching the block (17) is formed in the bottom of the linkage rod (11), so that the block (17) can be slidably inserted into the square cavity, and the rotating wheel (12) can be inserted into the limiting rod (13) through the limiting hole or the rotating wheel (12) can be separated from the limiting rod (13); A spring (19) is provided in the square cavity, the upper end of the spring (19) is fixedly connected to the bottom of the block (17), and the lower end of the spring (19) is fixedly connected to the bottom surface of the square cavity.

2. The trench excavation safety protection device according to claim 1, characterized in that: The support plate body comprises a support plate (1), a movable plate (7) and a lifting mechanism; the lower portion of the movable plate (7) is liftably inserted into the upper cavity of the support plate (1) through the lifting mechanism; the bottom of the support plate (1) forms a wedge-shaped surface that is wide at the top and narrow at the bottom; the top of the movable plate (7) is provided with a lifting ring (8); the U-shaped block (4) is mounted on the inner wall of the support plate (1).

3. The trench excavation safety protection device according to claim 2, characterized in that: The lifting mechanism comprises a threaded rod (9), a transmission rod (14), a second bevel gear (15), a first bevel gear (16) and a knob (20); a screw hole matching the threaded rod (9) is formed at the lower portion of the movable plate (7), so that the upper end of the threaded rod (9) is matched and screwed into the movable plate (7), and the lower end of the threaded rod (9) is rotatably mounted in the cavity of the support plate (1); one end of the transmission rod (14) is rotatably mounted on the support plate (1) through the knob (20), and the other end of the transmission rod (14) extends into the cavity and is coaxially fixedly connected to the second bevel gear (15); the first bevel gear (16) is coaxially fixedly connected to the threaded rod (9) and is meshed and transmission-connected with the second bevel gear (15).

4. The trench excavation safety protection device according to claim 3, characterized in that: A handwheel groove is formed on the outer wall of the support plate (1), and the knob (20) is concealedly installed in the handwheel groove.

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