Clamping mechanism for concrete block construction
By designing a clamping mechanism for concrete block construction, including auxiliary moving components, auxiliary support components and push components, the problem of difficult placement and alignment of concrete blocks in the prior art is solved, automatic alignment and support are achieved, and construction efficiency is improved.
Patent Information
- Application Number
- CN202411734805.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-29
- Publication Date
- 2025-03-11
AI Technical Summary
The clamping components of existing crane configurations cannot be aligned and adjusted during the placement of concrete blocks, resulting in inefficient construction and increasing the labor intensity of staff.
A clamping mechanism including an auxiliary moving assembly, an auxiliary support assembly and a push assembly is designed to realize automatic alignment and support of concrete blocks through the cooperation of hydraulic cylinders, rotary shafts and elastic members.
Automatic alignment and support of concrete blocks during construction is realized, construction efficiency is improved, labor intensity for staff is reduced, and accurate placement of blocks is ensured.
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Figure CN119590978A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of on-site transport equipment for building components, and in particular to a clamping mechanism used for concrete block construction. Background Art
[0002] During the construction of national highways, in order to prevent rainwater from flowing down from the mountains and concentrating on the road surface, forming a hazard to driving safety, open drainage ditches are generally used. Large, uniformly standardized concrete blocks are then clamped and assembled on-site using a crane and a clamping assembly. The clamping assembly configured on the current crane cannot align the blocks from the on-site block stacking area to the construction site. Workers also need to use crowbars to move and align the concrete blocks, which increases the workload. Therefore, it is necessary to design a clamping mechanism for concrete block construction that can assist in adjustment to solve the above problems. Summary of the Invention
[0003] In order to overcome the disadvantage that the clamping assembly of the current crane configuration cannot align and place the blocks when clamping them from the on-site block stacking area to the construction placement and assembly, and the workers need to use crowbars to move and align the concrete blocks, which increases a lot of workload, the technical problem is to provide a clamping mechanism for concrete block construction that can assist in adjustment.
[0004] The technical solution is: a clamping mechanism for concrete block construction, including a base plate, a U-shaped plate, a lifting ring, a mounting seat, a hydraulic cylinder, a first rotating shaft, a swing arm, a second rotating shaft, a splint, an auxiliary moving assembly, an auxiliary support assembly and a pushing assembly. A U-shaped plate is provided on the top of the base plate, a lifting ring is provided on the top of the U-shaped plate, a mounting seat is symmetrically provided on the top of the base plate, a hydraulic cylinder is rotatably provided on the mounting seat, a first rotating shaft is rotatably provided on the left and right side walls of the base plate, a swing arm is provided on the first rotating shaft, the upper end of the swing arm is rotatably connected to the telescopic rod of the hydraulic cylinder, a second rotating shaft is rotatably provided at the bottom of the swing arm, a splint is provided on the second rotating shaft, an auxiliary moving assembly that can adjust the installation position is provided on the base plate, an auxiliary support assembly that can support the bottom of the concrete block is provided on the splint, and a pushing assembly is provided on the auxiliary moving assembly, which can drive the auxiliary support assembly to move to support the bottom of the concrete block.
[0005] In addition, it is particularly preferred that the auxiliary moving component includes guide columns, slides, cross frames, connecting rods and universal wheels, two guide columns are symmetrically arranged on the left and right sides of the base plate, slides are slidably arranged on the two guide columns on the left and the two guide columns on the right, a cross frame is symmetrically arranged between the two slides, connecting rods are arranged on the left and right sides of the two cross frames, and universal wheels are arranged at the bottom ends of the connecting rods.
[0006] In addition, it is particularly preferred that the auxiliary support assembly includes a mounting frame, a guide sleeve, a lifting rod, a mounting plate, a guide rod, a movable frame, a support plate and a first elastic member, a mounting frame is provided at one end of the two splints away from each other, a guide sleeve is symmetrically embedded in the top of the mounting frame, lifting rods are slidably arranged in the guide sleeves, a mounting plate is provided between the bottom ends of the lifting rods on the same side, guide rods are symmetrically arranged horizontally front and back on the mounting plate, movable frames are slidably arranged on the guide rods, a support plate is provided between the movable frames on the same side, a first elastic member is sleeved on the lifting rod, one end of the first elastic member is connected to the guide sleeve, and the other end of the first elastic member is connected to the top of the lifting rod.
[0007] In addition, it is particularly preferred that the pushing assembly includes a connecting frame, a guide groove plate and a guide shaft, a connecting frame is provided on the lower side of the connecting rod, the connecting frame is connected to the guide groove plate, and a guide shaft that can be connected to the guide groove plate is provided on the movable frame.
[0008] In addition, it is particularly preferred that the slot entrance position of the guide slot plate is in a trumpet-shaped inclination.
[0009] In addition, it is particularly preferred that a guide assembly is also included, which includes a slide rail, a slider, a guide plate, a column, a fixed plate, a movable column, a fixed frame, a second elastic member, and a circular frame. Slide rails are provided at positions close to the top of the two mounting frames, and sliders are symmetrically slidably provided in the slide rails. Guide plates are provided on the side of the slider close to the bottom plate, and columns are provided on the top of the slider. A fixed plate is provided at the center of the top of the slide rail, and a movable column is horizontally slidably provided on the upper part of the fixed plate. A fixed frame is provided at the end of the movable column away from the bottom plate, and a second elastic member is symmetrically provided between the fixed frame and the fixed plate. A circular frame is symmetrically provided on the front and back of the bottom of the fixed frame, and the circular frame is slidably matched with the adjacent columns.
[0010] In addition, it is particularly preferred that a lifting assembly is also included, the lifting assembly includes a mounting column, a third rotating shaft, a rocker arm, a torsion spring, a shift rod, and a circular shaft, the mounting columns are symmetrically arranged on the top of the base plate about the mounting seat, the third rotating shaft is rotatably arranged on the upper part of the mounting column, the rocker arm is arranged at one end of the two third rotating shafts on the same side, the torsion spring is sleeved on the third rotating shaft, one end of the torsion spring is connected to the mounting column, and the other end of the torsion spring is connected to the rocker arm, the circular shaft is horizontally arranged on the upper part of the swing arm, the circular shaft is located on the upper side of the rocker arm, and the shift rod is provided at the end of the third rotating shaft away from each other, and the shift rod is in contact with the lower part of the adjacent skateboard.
[0011] Furthermore, it is particularly preferred that protrusions are evenly spaced apart on the facing sides of the splint.
[0012] Compared with the prior art, the present invention has the following advantages: 1. The clamping mechanism provided by the present invention, through the design of auxiliary moving components, auxiliary support components and pushing components, can automatically adjust the position of the concrete block when the crane clamps the concrete block to the construction position. The design of the auxiliary support component and the pushing component can automatically support and move the bottom of the concrete block during the clamping process to ensure that the block can be accurately aligned and placed.
[0013] 2. The guide assembly of this clamping mechanism automatically adjusts the position of the guide plate during the clamping process, ensuring that the concrete block can be smoothly aligned with the installed block, avoiding construction problems caused by inaccurate alignment. The lifting assembly automatically adjusts the position of the slide plate and universal wheel when the crane raises or lowers the clamping mechanism, ensuring smooth movement of the clamping mechanism and avoiding safety hazards caused by shaking or instability. BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Figure 1 This is a schematic structural diagram of the first state of the present invention.
[0015] Figure 2 This is a schematic diagram of the second state structure of the present invention.
[0016] Figure 3 This is a schematic diagram of the installation structure of the auxiliary movement component of the present invention.
[0017] Figure 4 Schematic diagram of the installation structure of the auxiliary support assembly of the present invention.
[0018] Figure 5 This is a schematic diagram of the installation structure of the guide assembly of the present invention.
[0019] Figure 6 It is a schematic diagram of the three-dimensional structure of the guide assembly of the present invention.
[0020] Figure 7 It is a schematic diagram of the installation structure of the lifting assembly of the present invention.
[0021] Figure 8 It is a partial structural schematic diagram of the pushing component of the present invention.
[0022] Figure numbers: 1, bottom plate, 2, U-shaped plate, 3, lifting ring, 4, mounting base, 5, hydraulic cylinder, 6, first rotating shaft, 7, swing arm, 8, second rotating shaft, 9, clamping plate, 10, auxiliary moving assembly, 101, guide column, 102, slide plate, 103, cross frame, 104, connecting rod, 105, universal wheel, 11, auxiliary support assembly, 111, mounting frame, 112, guide sleeve, 113, lifting rod, 114, mounting plate, 115, guide rod, 116, moving frame, 117, support plate, 118 , first elastic member, 12, pushing assembly, 121, connecting frame, 122, guide groove plate, 123, guide shaft, 13, guide assembly, 131, slide rail, 132, slider, 133, guide plate, 134, column, 135, fixed plate, 136, movable column, 137, fixed frame, 138, second elastic member, 139, circular frame, 14, lifting assembly, 141, mounting column, 142, third rotating shaft, 143, rocker arm, 144, torsion spring, 145, shift rod, 146, circular shaft. DETAILED DESCRIPTION
[0023] The present invention will be further described below with reference to the embodiments shown in the accompanying drawings.
[0024] Example: Figure 1 、 Figure 2 、 Figure 3 and Figure 4 As shown, a clamping mechanism for concrete block construction includes a base plate 1, a U-shaped plate 2, a lifting ring 3, a mounting seat 4, a hydraulic cylinder 5, a first rotating shaft 6, a swing arm 7, a second rotating shaft 8, a clamping plate 9, an auxiliary moving component 10, an auxiliary supporting component 11 and a pushing component 12. A U-shaped plate 2 is provided on the top of the base plate 1, a plurality of lifting rings 3 are provided on the top of the U-shaped plate 2, and an anti-slip belt is wound around the lifting ring 3. The lifting rings 3 are respectively arranged at the four corner positions of the top of the U-shaped plate 2 and the center position of the top of the U-shaped plate 2. A mounting seat 4 is symmetrically provided on the top of the base plate 1, and a hydraulic cylinder 5 is rotatably provided on the mounting seat 4. The left and right side walls of the base plate 1 are both rotatable. A first rotating shaft 6 is provided, and a swing arm 7 is provided on the first rotating shaft 6. The upper end of the swing arm 7 is rotatably connected to the telescopic rod of the hydraulic cylinder 5. The bottom of the swing arm 7 is rotatably provided with a second rotating shaft 8, and a clamping plate 9 is provided on the second rotating shaft 8. The facing sides of the clamping plate 9 are evenly spaced with protrusions. An auxiliary moving component 10 that can adjust the installation position is provided on the bottom plate 1, and an auxiliary supporting component 11 that can support the bottom of the concrete block is provided on the clamping plate 9. A pushing component 12 is provided on the auxiliary moving component 10, and the pushing component 12 can drive the auxiliary supporting component 11 to move to support the bottom of the concrete block.
[0025] like Figure 1 、 Figure 2 and Figure 3As shown, the auxiliary moving component 10 includes a guide column 101, a slide 102, a cross frame 103, a connecting rod 104 and a universal wheel 105. Two guide columns 101 are symmetrically arranged on the left and right sides of the base plate 1. Slides 102 are slidably arranged on the two guide columns 101 on the left and the two guide columns 101 on the right. A cross frame 103 is symmetrically arranged between the two slides 102. Connecting rods 104 are arranged on the left and right sides of the two cross frames 103. Universal wheels 105 are arranged at the bottom ends of the connecting rods 104, which facilitate the movement and alignment of concrete blocks.
[0026] like Figure 1 、 Figure 2 、 Figure 3 、 Figure 4 and Figure 7 As shown, the auxiliary support assembly 11 includes a mounting frame 111, a guide sleeve 112, a lifting rod 113, a mounting plate 114, a guide rod 115, a movable frame 116, a support plate 117 and a first elastic member 118. The two splints 9 are each provided with a mounting frame 111 at one end away from each other. The top of the mounting frame 111 is symmetrically embedded with a guide sleeve 112. The lifting rod 113 is slidably arranged in the guide sleeve 112. A mounting plate 114 is provided between the bottom ends of the lifting rods 113 on the same side. Guide rods 115 are symmetrically arranged on the mounting plate 114 horizontally and front to back. Moving frames 116 are slidably arranged on the guide rods 115. A support plate 117 is provided between the moving frames 116 on the same side. A first elastic member 118 is sleeved on the lifting rod 113. The first elastic member 118 is a tension spring. One end of the first elastic member 118 is connected to the guide sleeve 112, and the other end of the first elastic member 118 is connected to the top of the lifting rod 113.
[0027] like Figure 1 、 Figure 2 、 Figure 4 and Figure 8 As shown, the pushing assembly 12 includes a connecting frame 121, a guide groove plate 122 and a guide shaft 123. The connecting frame 121 is provided on the lower side of the connecting rod 104, and the connecting frame 121 is connected to the guide groove plate 122. The movable frame 116 is provided with a guide shaft 123 that can be connected to the guide groove plate 122. The groove entrance position of the guide groove plate 122 is inclined in a horn shape.
[0028] like Figure 1 、 Figure 2 、 Figure 5 and Figure 6As shown, the guide assembly 13 is also included. The guide assembly 13 includes a slide rail 131, a slider 132, a guide plate 133, a column 134, a fixed plate 135, a movable column 136, a fixed frame 137, a second elastic member 138, and a circular frame 139. The two installation frames 111 are both provided with a slide rail 131 at a position close to the top. The slide rails 131 are both symmetrically slidably provided with sliders 132. The sliders 132 are both provided with guide plates 133 on the side close to the bottom plate 1. A column 134 is provided on the top of each block 132, a fixed plate 135 is provided at the center of the top of the slide rail 131, a movable column 136 is provided on the upper part of the fixed plate 135 in a horizontal sliding manner, a fixed frame 137 is provided at the end of the movable column 136 away from the bottom plate 1, a second elastic member 138 is symmetrically provided between the fixed frame 137 and the fixed plate 135, and a circular frame 139 is symmetrically provided at the bottom of the fixed frame 137, and the circular frame 139 is slidably matched with the adjacent column 134.
[0029] like Figure 1 、 Figure 2 and Figure 7 As shown, it also includes a lifting component 14, which includes a mounting column 141, a third rotating shaft 142, a rocker rod 143, a torsion spring 144, a lever 145, and a circular shaft 146. The mounting columns 141 are symmetrically arranged on the top of the base plate 1 about the mounting seat 4. The third rotating shaft 142 is rotatably arranged on the upper part of the mounting column 141, and the rocker rod 143 is arranged at the adjacent end of the two third rotating shafts 142 on the same side. A torsion spring 144 is sleeved on the third rotating shaft 142, one end of the torsion spring 144 is connected to the mounting column 141, and the other end of the torsion spring 144 is connected to the rocker rod 143. A circular shaft 146 is horizontally arranged on the upper part of the swing arm 7, and the circular shaft 146 is located on the upper side of the rocker rod 143. The ends of the third rotating shafts 142 away from each other are provided with a lever 145, and the lever 145 contacts and cooperates with the lower part of the adjacent skateboard 102.
[0030] When it is necessary to lay concrete blocks in the open drainage ditch beside the road for protection, the staff first binds the hook of the crane to the lifting ring 3 of the clamping mechanism. Then, the staff manually operates the crane to move the clamping mechanism above the concrete block. The staff manually adjusts the two swing arms 7 to move downward along the two side walls of the concrete block. Then, by controlling the extension of the hydraulic cylinder 5, the extension of the hydraulic cylinder 5 drives the upper part of the swing arm 7 to swing away from the bottom plate 1. As the upper part of the swing arm 7 swings away from the bottom plate 1, the circular shaft 146 is driven to disengage the swing rod 143. The swing rod 143 is no longer stressed, and the torsion spring 144 is reset. The third rotating shaft 142 drives the swing rod 143 and the shifting rod 145 to swing. The shifting rod 145 no longer supports the slide plate 102. The moving assembly moves downward under the action of gravity until the universal wheel 105 contacts the ground. When the hydraulic cylinder 5 is controlled to continue to extend, the lower parts of the two swing arms 7 drive the clamping plates 9 to move closer to each other. Since the clamping plates 9 are rotatably connected to the lower parts of the swing arms 7 through the second rotating shaft 8, the clamping plates 9 can automatically adjust their angles to clamp the concrete block after contacting the side walls of the concrete block. When the clamping plates 9 clamp the concrete block, the support plate 117 just rests on the lower side walls of the concrete block, and the guide shaft 123 is located at the slot entrance position of the guide slot plate 122. At the same time, the side walls of the concrete block will squeeze the movable column 136 to move toward the position of the fixed plate 135. The second elastic member 138 is stretched, and the fixed plate 135 drives the circular frame 139 to move synchronously through the fixed frame 137. The circular frame 139 squeezes the column 134, and then the column 134 drives the slider 132 to move backward, and then the slider 132 drives the guide plate 133 to move backward and extend forward and backward for subsequent docking of the installed concrete blocks, so as to facilitate adjustment of the position where the concrete blocks need to be placed. When the crane drives the clamping mechanism to clamp the concrete block and move it upward, the auxiliary moving assembly 10 continues to move downward under the action of gravity. At this time, the entrance inclined surface of the guide groove plate 122 will squeeze the guide shaft 123, and the guide shaft 123 drives the movable frame 116, the guide rod 115, the mounting plate 114, the support plate 117 and the lifting rod 113 to move downward. The first elastic member 118 is compressed, and then the clamping mechanism continues to rise. The auxiliary moving assembly 10 continues to move downward to squeeze the guide shaft 123, and the guide shaft 123 will slide along the groove of the guide groove plate 122, and then the two support plates 117 move toward each other to control the bottom of the concrete block, thereby limiting the bottom of the concrete block to prevent accidental sliding from high altitude.
[0031] When it moves to the approximate position of the drainage ditch, the crane is started to lower the clamping mechanism. When the universal wheel 105 contacts both sides of the ditch, the staff can push and adjust it according to the on-site conditions so that the concrete block fits the assembled concrete block. Since the outer side of the guide plate 133 is inclined, the two front guide plates 133 are trumpet-shaped. When the inclined surface of the guide plate 133 first contacts the edge of the assembled concrete block, the two guide plates 133 can play a guiding role and continue to push the clamping mechanism. Finally, the two guide plates 133 are vertically clamped on both sides of the assembled concrete block, and the two concrete blocks are aligned and fit together. At this time, the staff controls the crane to drive the clamping mechanism to be placed downward, and the auxiliary moving assembly 10 moves upward relatively, and then gradually squeezes the guide shaft 123 to move outward. When the guide shaft 123 moves to the entrance inclined surface position of the guide groove plate 122, the first elastic member 118 is reset, thereby driving When the guide shaft 123 moves away from the entrance inclined surface of the guide groove plate 122, the first elastic member 118 is reset, and then the movable frame 116, guide rod 115, mounting plate 114, support plate 117 and lifting rod 113 are driven to move upward and reset through the guide shaft 123. The resetting of the swing arm 7 will drive the circular shaft 146 to squeeze the swing rod 143 to reset, the torsion spring 144 to reset, the third rotating shaft 142 to rotate in the opposite direction, the torsion spring 144 to deform, the shift rod 145 to swing upward to drive the slide plate 102 to move upward, and then the cross frame 103, the connecting rod 104 and the universal wheel 105 to move upward and reset. This device can quickly complete the clamping and placement of concrete blocks, can play a guiding role in docking, and is convenient for transportation and assembly.
[0032] It should be understood that this embodiment is only used to illustrate the present invention and is not used to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms fall equally within the scope limited by the appended claims of the application.
Claims
1. A clamping mechanism for concrete block construction, characterized by: The invention comprises a bottom plate (1), a U-shaped plate (2) is arranged on the top of the bottom plate (1), a lifting ring (3) is arranged on the top of the U-shaped plate (2), a mounting seat (4) is symmetrically arranged on the top of the bottom plate (1), a hydraulic cylinder (5) is rotatably arranged on the mounting seat (4), a first rotating shaft (6) is rotatably arranged on the left and right side walls of the bottom plate (1), a swing arm (7) is arranged on the first rotating shaft (6), the upper end of the swing arm (7) is rotatably connected to the telescopic rod of the hydraulic cylinder (5), and the bottom of the swing arm (7) is rotatably connected to the telescopic rod of the hydraulic cylinder (5). The second rotating shaft (8) is rotatably provided on the bottom plate (1), a clamping plate (9) is provided on the second rotating shaft (8), an auxiliary moving component (10) capable of adjusting the installation position is provided on the bottom plate (1), the clamping plate (9) is provided with an auxiliary supporting component (11) capable of supporting the bottom of the concrete block, the auxiliary moving component (10) is provided with a pushing component (12), and the pushing component (12) can drive the auxiliary supporting component (11) to move to support the bottom of the concrete block.
2. A clamping mechanism for concrete block construction according to claim 1, characterized in that: The auxiliary moving component (10) comprises a guide column (101), wherein two guide columns (101) are symmetrically arranged on the bottom plate (1), a slide plate (102) is slidably arranged on the two guide columns (101) on the left side and the two guide columns (101) on the right side, a cross frame (103) is symmetrically arranged between the two slide plates (102), and connecting rods (104) are arranged on the left and right sides of the two cross frames (103), and a universal wheel (105) is arranged at the bottom end of the connecting rod (104).
3. A clamping mechanism for concrete block construction according to claim 2, characterized in that: The auxiliary support assembly (11) comprises a mounting frame (111), the mounting frame (111) being disposed at one end of the two clamping plates (9) away from each other, a guide sleeve (112) being embedded and symmetrically disposed on the top of the mounting frame (111), a lifting rod (113) being slidably disposed in the guide sleeve (112), a mounting plate (114) being disposed between the bottom ends of the lifting rods (113) on the same side, a guide rod (115) being symmetrically disposed on the mounting plate (114), a movable frame (116) being slidably disposed on the guide rod (115), a support plate (117) being disposed between the movable frames (116) on the same side, a first elastic member (118) being sleeved on the lifting rod (113), one end of the first elastic member (118) being connected to the guide sleeve (112), and the other end of the first elastic member (118) being connected to the top of the lifting rod (113).
4. A clamping mechanism for concrete block construction according to claim 3, characterized in that: The pushing assembly (12) comprises a connecting frame (121), the connecting frame (121) is arranged on the lower side of the connecting rod (104), the connecting frame (121) is connected to a guide groove plate (122), and the moving frame (116) is provided with a guide shaft (123) capable of connecting with the guide groove plate (122).
5. A clamping mechanism for concrete block construction according to claim 4, characterized in that: The slot body entrance position of the guide slot plate (122) is in a trumpet-shaped inclination.
6. A clamping mechanism for concrete block construction according to claim 5, characterized in that: Also includes A guide assembly (13) is provided, the guide assembly (13) comprising a slide rail (131), the slide rails (131) are arranged at positions close to the tops of the two installation frames (111), the slide rails (131) are symmetrically slidably arranged with sliders (132) in the slide rails (131), the sliders (132) are arranged with guide plates (133) on one side close to the bottom plate (1), the tops of the sliders (132) are arranged with columns (134), and the top center of the slide rails (131) is provided with a fixing plate (133). 35), a movable column (136) is horizontally slidably arranged on the upper part of the fixed plate (135), a fixed frame (137) is arranged at one end of the movable column (136) away from the bottom plate (1), a second elastic member (138) is symmetrically arranged between the fixed frame (137) and the fixed plate (135), and a circular frame (139) is symmetrically arranged at the bottom of the fixed frame (137), and the circular frame (139) is slidably matched with the adjacent column (134).
7. A clamping mechanism for concrete block construction according to claim 6, characterized in that: The lifting assembly (14) further comprises a lifting assembly (14), the lifting assembly (14) comprising a mounting column (141), the mounting column (141) being symmetrically arranged on the top of the base plate (1) with respect to the mounting seat (4) in a front-rear manner, the mounting column (141) being rotatably arranged on the upper part of each of the mounting columns (141), a swing rod (143) being arranged on the adjacent ends of two third rotating shafts (142) on the same side, the third rotating shafts (142) being sleeved with a torsion spring (144), the One end of the torsion spring (144) is connected to the mounting column (141), and the other end of the torsion spring (144) is connected to the swing rod (143). A round shaft (146) is transversely arranged on the upper part of the swing arm (7), and the round shaft (146) is located on the upper side of the swing rod (143). A lever (145) is arranged at one end of the third rotating shaft (142) that is away from each other, and the lever (145) is in contact with the lower part of the adjacent slide plate (102).
8. A clamping mechanism for concrete block construction according to claim 7, characterized in that: The facing sides of the clamping plate (9) are provided with protrusions at even intervals.