Wooden bridge bearing capacity experiment device for science popularization

Abstract

The utility model discloses a wooden bridge bearing capacity experiment device for science popularization, which comprises a vertical frame and an electric push rod, the electric push rod is arranged at the bottom in the vertical frame, a push rod of the electric push rod is arranged upwards, an external push-pull force display instrument is arranged at the end part of the electric push rod, and a lower cross rod is arranged at the upper end of the external push-pull force display instrument. Vertical rods are arranged at the two ends of the lower cross rod respectively, an upper cross rod is arranged above the lower cross rod, the upper ends of the vertical rods are connected with the upper cross rod, a short rod and a pressing block are sequentially arranged in the middle of the upper cross rod, and a displayer communicated with the external push-pull force displayer is arranged on the vertical frame. In conclusion, the device has the advantages of being convenient to operate, high in experiment efficiency and accurate in detection.

Description

Technical Field

[0001] The utility model relates to the technical field of wooden bridge load-bearing experiments, in particular to a wooden bridge load-bearing capacity experimental device for popular science. Background Art

[0002] In recent years, the popularization of science and technology among young people has received increasing attention. Many schools and institutions have launched various hands-on activities to help students master the underlying scientific principles. The wooden bridge load-bearing experiment is one such interesting and meaningful activity. Students can build a wooden bridge by hand and then use a load-bearing test device to test its load-bearing capacity.

[0003] At present, some popular science wooden bridge load-bearing test devices are implemented in the form of hanging weights, which has problems such as inconvenient operation and large errors. When the weights are continuously added, causing the bridge to break, the splashing of wood chips from the broken bridge and the rebound of the weights pose certain safety hazards. In addition, the measurement of the weights is time-consuming and labor-intensive, and the experimental efficiency is relatively low. Some popular science wooden bridge load-bearing test devices use the method of manually twisting the threaded sleeve to provide the downward pressure on the bridge. However, the implementation process of this method is greatly affected by human factors such as the manual rotation force and the speed of rotation. In addition, when conducting experimental tests on a large number of experimental bridges, multiple people need to take turns working, which will undoubtedly increase the error of the experiment. Therefore, it is an objective need to develop a popular science wooden bridge load-bearing capacity test device that is easy to operate, has high experimental efficiency, and can accurately detect. Utility Model Content

[0004] The purpose of the utility model is to provide a popular science wooden bridge load-bearing capacity experimental device which is easy to operate, has high experimental efficiency and accurate detection.

[0005] The purpose of the present utility model is achieved in this way, including a stand and an electric push rod, the upper parts of both sides of the stand are provided with cross beams, the electric push rods are installed at the bottom of the stand, the push rods of the electric push rods are arranged upward, and the push rod ends of the electric push rods are provided with an external push-pull force display, the upper end of the external push-pull force display is provided with a lower cross bar, the two ends of the lower cross bar are respectively provided with stand bars, an upper cross bar is provided above the lower cross bar, the upper end of the stand bar is connected to the upper cross bar, the middle part of the upper cross bar is sequentially provided with a short rod and a pressure block, and the stand is provided with a display connected to the external push-pull force display.

[0006] Furthermore, transparent acrylic protective plates are hinged on the upper ends of both sides of the stand.

[0007] Furthermore, ladders are provided on both sides of the stand.

[0008] Furthermore, transverse rails are symmetrically provided on the upper parts of both sides of the vertical frame, and the two ends of the crossbeam are slidingly connected to the corresponding transverse rails.

[0009] Furthermore, the push rod of the electric push rod is provided with scale lines along its length direction.

[0010] Furthermore, optical axis fixing clamps are installed on the upper crossbar and the lower crossbar, and the vertical poles are mounted on the optical axis fixing clamps.

[0011] Furthermore, a linear bearing is installed on the stand, and the upright rod is installed in the linear bearing.

[0012] Furthermore, a scale is provided on the outer side of each beam.

[0013] The utility model is used for a popular science experiment on the bearing capacity of a wooden bridge. Before starting the bearing test, two workers first place the wooden bridge to be tested on the two crossbeams of the vertical frame. At this time, the wooden bridge spans between the two crossbeams, and the crossbeams play the role of supporting both ends of the wooden bridge. After the wooden bridge is placed stably, the electric push rod is started, and the push rod retracts and moves downward, driving the external push-pull force display instrument, the lower crossbar, the vertical rod and the upper crossbar to move downward in sequence. Synchronously, the short rod and the pressure block move downward until the pressure block is pressed on the wooden bridge. The pressure block continues to move downward under the drive of the electric push rod. At this time, the two ends of the wooden bridge are respectively placed on the two crossbeams, and the middle part is subjected to the downward force exerted on it by the pressure block, so that the wooden bridge is continuously deformed until it breaks. The external push-pull force display instrument and the display sense and record the magnitude and change of the force applied to the wooden bridge in the process from being subjected to force to being broken, and record the value of the maximum force, thereby obtaining the bearing capacity of the wooden bridge and achieving the experimental purpose. After the experiment is completed, the electric push rod drives the pressure block to move up and reset, and wait for the start of another experiment. During the experiment, this device eliminates the form of hanging weights in the existing experimental device and adopts a matching external push-pull force display and display. The detected force will be intuitively displayed on the display. Compared with the weight measurement method, the detected value is more accurate, the implementation process is more convenient and quick, and the experimental efficiency is higher. Secondly, in this device, the force used to break the wooden bridge comes from the electric push rod, which eliminates the method of manually twisting the threaded sleeve to provide power in the existing technology, eliminating the influence of various human factors. It is also suitable for the experimental detection of a large number of experimental bridges. There is no need for multiple people to take turns working, and the operation is more convenient, which can improve the experimental efficiency and the stability of the experimental data. There is no problem of the force fluctuating, and the experimental error is reduced. In summary, the utility model has the advantages of easy operation, high experimental efficiency, and accurate detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the overall structure of the utility model;

[0015] In the figure: 1-stand, 2-electric push rod, 3-crossbeam, 4-scale, 5-external push-pull force display, 6-lower crossbar, 7-vertical pole, 8-upper crossbar, 9-short rod, 10-pressure block, 11-display, 12-transparent acrylic protective plate, 13-ladder, 14-cross track, 15-scale line, 16-optical axis fixing clamp, 17-linear bearing. DETAILED DESCRIPTION

[0016] The present invention will be further described below in conjunction with the accompanying drawings, but the present invention is not limited in any way. Any changes or improvements based on the present invention fall within the scope of protection of the present invention.

[0017] like Figure 1 As shown, the utility model includes a stand 1 and an electric push rod 2. The stand 1 can be welded by square tubes of the same specification, with a simple structure, less materials and high strength. It can also be made of other materials according to actual conditions. The electric push rod 2 is a prior art. After power is turned on, the push rod can be extended or shortened as needed under the force state. The three-position switch can be used to freely control the rise, fall and pause. The upper part of both sides of the stand 1 is provided with a crossbeam 3. The electric push rod 2 is installed at the bottom of the stand 1. In order to ensure that the wooden bridge can bear the force better, The electric push rod 2 can be installed at the center of the bottom of the vertical frame 1. The push rod of the electric push rod 2 is arranged upward, and the push rod end of the electric push rod 2 is provided with an external push-pull force display 5. The upper end of the external push-pull force display 5 is provided with a lower cross bar 6, and the two ends of the lower cross bar 6 are respectively provided with vertical rods 7. An upper cross bar 8 is provided above the lower cross bar 6. The upper end of the vertical rod 7 is connected to the upper cross bar 8. The middle part of the upper cross bar 8 is sequentially provided with a short rod 9 and a pressure block 10. The vertical frame 1 is provided with a display 11 connected to the external push-pull force display 5. The external push-pull force display 5 and the display 11 are supporting instruments and can be purchased and installed on the market. When the electric push rod 2 is installed, its upper part can be connected to the external push-pull force display 5 by bolts, and the lower part can be fixed to the bottom of the vertical frame 1 by flanges and bolts.

[0018] The utility model is used for the popular science experiment of the load-bearing capacity of wooden bridges. Before starting the load-bearing test, two workers first place the wooden bridge to be tested on the two crossbeams 3 of the stand 1. At this time, the wooden bridge spans between the two crossbeams 3, and the crossbeams 3 play the role of supporting both ends of the wooden bridge. After the wooden bridge is placed stably, the electric push rod 2 is started, and the push rod retracts and moves downward, driving the external push-pull force display 5, the lower cross bar 6, the vertical bar 7 and the upper cross bar 8 to move downward in turn. Synchronously, the short rod 9 and the pressure block 10 move downward until the pressure block 10 presses the wooden bridge. On the other hand, the pressing block 10 continues to move downward under the drive of the electric push rod 2. At this time, the two ends of the wooden bridge are respectively placed on the two cross beams 3, and the middle part is subjected to the downward force exerted by the pressing block 10, which makes the wooden bridge continuously deformed until it breaks. The external push-pull force display 5 and the display 11 sense and record the magnitude and change of the force applied to the wooden bridge in the process from force to fracture, and record the value of the maximum force, thereby obtaining the bearing capacity of the wooden bridge and achieving the experimental purpose. After the experiment is completed, the electric push rod 2 drives the pressing block 10 to move up and reset, waiting for the start of another experiment. During the experiment, the present device eliminates the form of hanging weights in the existing experimental device and adopts a matching external push-pull force display 5 and display 11. The detected force will be intuitively displayed on the display 11, and the detection data is visualized. Compared with the weight measurement method, the detected value is more accurate, the implementation process is more convenient and quick, and the experimental efficiency is higher. Secondly, in the present device, the force for breaking the wooden bridge comes from the electric push rod 2, which can drive the pressure block 10 to move downward at a constant speed, eliminating the method of manually twisting the threaded sleeve to provide power in the existing technology, eliminating the influence of various human factors, and is also suitable for the experimental detection of a large number of experimental bridges. There is no need for multiple people to take turns working, and the operation is more convenient, which can improve the experimental efficiency and the stability of the experimental data. There is no problem of the force fluctuating, which reduces the experimental error and saves time and effort. In addition, the wooden bridge load-bearing experimental device designed by the present utility model has a wide range of applications. It can be used not only in teaching and popular science work, but also as a detection platform to detect the force of workpieces.

[0019] Transparent acrylic protective plates 12 are hinged at the upper ends of both sides of the frame 1. This experimental device is used to test the load-bearing capacity of wooden bridges. The wooden bridge needs to be broken. When the wooden bridge is broken, some wood chips and debris will often fly up, which poses a certain safety hazard. In order to solve this problem, a transparent acrylic protective plate 12 is set. During the experiment, the transparent acrylic protective plate 12 is rotated so that its end is tilted downward to block impurities such as wood chips and debris that fly up when the wooden bridge breaks, thereby improving the safety during the experiment. At the same time, it is made of transparent acrylic material and will not affect the observation of the experimental process. When placing the wooden bridge, the transparent acrylic protective plate 12 is flipped upward to leave enough space for the placement of the wooden bridge.

[0020] Preferably, ladders 13 are provided on both sides of the frame 1. During operation of the utility model, two workers are required to first place the wooden bridge to be inspected on the two beams 3 of the frame 1. Ladders 13 are provided on both sides of the frame 1 to facilitate workers of different heights to place the wooden bridge to the required position more conveniently, and the applicability is higher.

[0021] Since the height of the frame 1 is usually high, for the convenience of operation, ladders 13 need to be set on both sides of the frame 1. During the operation, two staff members are required to place the wooden bridge to be inspected on the two beams 3 of the frame 1. On the one hand, due to the different heights of the staff members, on the other hand, in order to facilitate the placement of the wooden bridge to the required position, ladders 13 need to be set on both sides of the frame 1 for easier operation.

[0022] During the same experiment, the lengths of all wooden bridges used for the experiment are fixed as specified. However, due to changes in relevant regulations or in different experimental processes, the required lengths of wooden bridges will vary. In this case, it is necessary to adjust the distance between the two beams 3 accordingly. To achieve this, transverse rails 14 are symmetrically provided on the upper parts of both sides of the stand 1, and the two ends of the beam 3 are slidably connected to the corresponding transverse rails 14. The two ends of the beam 3 are slidably installed on the two transverse rails 14. By sliding the beam 3 on the transverse rails 14, the distance between the two beams 3 is shortened or lengthened, thereby adapting to the experimental requirements of wooden bridges of different lengths and improving the applicability of the entire experimental device. In the actual production process, corresponding positioning mechanisms such as positioning bolts can also be provided on the transverse rails 14. When the position of the beam 3 is adjusted, they are used to position the beam 3 to prevent the beam 3 from sliding accidentally.

[0023] The push rod of the electric push rod 2 is provided with scale lines 15 along its length direction. The scale lines 15 can be used to observe the contraction of the push rod from the beginning of compression to the fracture of the wooden bridge, and then indirectly judge the bearing capacity of the wooden bridge. The scale lines 15 on the push rod are used to assist the external push-pull force display 5 in detecting the bearing capacity of the wooden bridge. The two are combined with each other to perform double comparison of data, thereby improving the detection effect of the bearing capacity of the wooden bridge. At the same time, when the external push-pull force display 5 and the display 11 are damaged, the scale lines 15 can also be used as a spare temporary replacement to ensure that the device can continue to be used. In short, the setting of the scale lines 15 can realize double numerical comparison during detection, thereby avoiding errors when the external push-pull force display 5 fails.

[0024] An optical axis fixing clamp 16 is installed on the upper cross bar 8 and the lower cross bar 6, and the vertical rod 7 is installed on the optical axis fixing clamp 16. In this device, the vertical rod 7 is fixed on the upper cross bar 8 and the lower cross bar 6, resulting in no relative displacement between the vertical rod 7 and the upper cross bar 8, and between the vertical rod 7 and the lower cross bar 6, making adjustment more difficult. When the height of the wooden bridge is high, the wooden bridge may not be placed in the predetermined position due to the low position of the pressure block 10. In order to solve this problem, an optical axis fixing clamp 16 is provided. The existing technology of the optical axis fixing clamp 16 is used for clamping the optical axis, and the optical axis is usually clamped by tightening the bolt and loosened by loosening the bolt. When the height of the pressure block 10 needs to be adjusted, it is only necessary to loosen the bolt, move the position of the upper cross bar 8 upward, and tighten the bolt after reaching the predetermined position.

[0025] A linear bearing 17 is installed on the stand 1, and the upright rod 7 is installed in the linear bearing 17. The linear bearing 17 is an existing technology and is a linear motion system produced at low cost. It is used for unlimited stroke and is used in conjunction with a cylindrical shaft. In this device, the upright rod 7 is installed in the linear bearing 17. Without affecting the free up and down movement of the upright rod 7, it can also guide and position the upright rod 7 to prevent the upright rod 7 from shifting, tilting and shaking. During the actual installation process, the installation quantity and installation position of the linear bearing 17 can be determined according to actual needs to ensure the normal operation of the experiment.

[0026] A scale 4 is provided on the outer surface of each crossbeam 3. When this device is used to test the load-bearing capacity of a wooden bridge, the wooden bridge to be tested is placed on two crossbeams 3. During actual operation, it was found that wooden bridges are easily placed askew, which in turn affects the accuracy of the actual data. Therefore, a scale 4 is provided to ensure that the wooden bridge is located in the middle of the stand 1 and directly below the pressure block 10, ensuring the normal progress of the experiment and the accuracy of the experimental data. In the present utility model, the scale 4 can be a metal scale that can be affixed to the crossbeam 3 of the stand 1. This facilitates the installation of the wooden bridge so that it is located in the center of the crossbeam 3 and ensures pressure balance.

Claims

1. A scientific and popular wooden bridge load-bearing capacity experimental device, comprising a stand (1) and an electric push rod (2), characterized in that : The upper part of both sides of the stand (1) is provided with a crossbeam (3), the electric push rod (2) is installed at the bottom of the stand (1), the push rod of the electric push rod (2) is arranged upward, and the push rod end of the electric push rod (2) is provided with an external push-pull force display (5), the upper end of the external push-pull force display (5) is provided with a lower cross bar (6), the two ends of the lower cross bar (6) are respectively provided with vertical rods (7), the upper end of the lower cross bar (6) is provided with an upper cross bar (8), the upper end of the vertical rod (7) is connected to the upper cross bar (8), the middle part of the upper cross bar (8) is provided with a short rod (9) and a pressure block (10) in sequence, and the stand (1) is provided with a display (11) connected to the external push-pull force display (5).

2. The load-bearing capacity experimental device for wooden bridges for popular science according to claim 1, characterized in that : The upper ends of both sides of the stand (1) are hinged with transparent acrylic protective plates (12).

3. The load-bearing capacity experimental device for wooden bridges for popular science according to claim 1, characterized in that Ladders (13) are provided on both sides of the stand (1).

4. The load-bearing capacity experimental device for wooden bridges for popular science according to claim 1, characterized in that : Transverse rails (14) are symmetrically provided on the upper parts of both sides of the stand (1), and the two ends of the crossbeam (3) are slidably connected to the corresponding transverse rails (14).

5. The load-bearing capacity experimental device for wooden bridges for popular science according to claim 1 is characterized in that The electric push rod (2) is provided with scale lines (15) along its length direction.

6. The load-bearing capacity experimental device for wooden bridges for popular science according to claim 1, characterized in that : The upper crossbar (8) and the lower crossbar (6) are mounted with an optical axis fixing clamp (16), and the vertical rod (7) is mounted on the optical axis fixing clamp (16).

7. The load-bearing capacity experimental device for wooden bridges for popular science according to claim 1, characterized in that A linear bearing (17) is mounted on the stand (1), and the stand (7) is mounted in the linear bearing (17).

8. The load-bearing capacity experimental device for wooden bridges for popular science according to claim 1, characterized in that : A scale (4) is provided on the outer side of each beam (3).

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