A mechanical experiment demonstration device

Abstract

The utility model discloses a mechanical experiment demonstration device, which belongs to the field of teaching experiment demonstration technology, and comprises a support seat, an angle measuring disc and a force measuring display assembly, wherein the angle measuring disc is fixed on the upper part of the support seat, and the force measuring display assembly is arranged on the support seat and the angle measuring disc; the force measuring display assembly comprises a display, a first tension sensor, a second tension sensor, a thin rope and a hook weight, the display is fixed on the angle measuring disc, and is electrically connected to the first tension sensor and the second tension sensor respectively, the first tension sensor and the second tension sensor are respectively connected to the upper sides of the support seat, and the positions of the first tension sensor and the second tension sensor on the support seat are adjustable, the two ends of the thin rope are respectively fixed on the first tension sensor and the second tension sensor, and the hook weight is hung on the thin rope. The utility model meets the needs of intuitive teaching, can help students effectively overcome the understanding obstacles of the problem of dynamic balance of concurrent forces, and is suitable for physics teaching.

Description

Technical Field

[0001] The utility model belongs to the technical field of teaching experiment demonstration, and specifically relates to a mechanics experiment demonstration device. Background Art

[0002] Concurrent forces are an important knowledge point in physics teaching. The curriculum standard clearly requires high school students to deeply understand the principles of force composition and decomposition through experimental activities, master the equilibrium conditions of concurrent forces, and distinguish between vectors and scalars. They also need to use this knowledge to analyze daily problems. However, when teaching complex problems such as the dynamic equilibrium of concurrent forces and the clothesline model, traditional teaching methods are often limited to blackboard writing and force diagrams. This teaching method is highly theoretical and relatively abstract, lacking the practical aspects of experimental exploration, which may cause students to have obstacles in understanding. For the experiment of "Parallelogram Law of Forces", although the experimental equipment provided by high school textbooks, such as spring dynamometers and rubber strips, can also be verified, manual reading of values ​​is prone to inaccurate results, and the demonstration and operation are cumbersome, which is not conducive to improving the quality of teaching.

[0003] In order to solve the above technical problems, a Chinese patent document with publication number CN206601864U discloses a force synthesis decomposition instrument, including: a force synthesis decomposition plate with a hollow middle; two arcs are symmetrically opened on the force synthesis decomposition plate, a horizontal beam that can be moved up and down along its vertical direction is movably arranged at the center of the force synthesis decomposition plate, a protractor that can be horizontally moved on the horizontal beam is arranged on the horizontal beam, a scale for viewing the moving distance when the horizontal beam moves is arranged on the force synthesis decomposition plate, and a plumb instrument is arranged on the force synthesis decomposition plate. Compared with traditional teaching methods, this patent document does provide new ideas for teaching and can verify the dynamic balance of three forces. However, in practical applications, in order to ensure that the error of the experiment is minimized, it is necessary to calibrate the movable parts such as the horizontal beam and the protractor in a cumbersome manner, which not only affects the continuity of teaching, but also makes the operation of the experimental demonstration complicated, making it difficult for students to intuitively focus on the synthesis and decomposition process of the force, thereby affecting the intuitiveness of the experimental demonstration. Therefore, it is difficult for this instrument to fully meet the needs of intuitive teaching.

[0004] Based on the above technical problems, it is necessary to design a mechanical experiment demonstration device with simple operation and intuitive demonstration to help students better understand and master the relevant concepts of concurrent forces, thereby promoting the improvement of teaching quality. Utility Model Content

[0005] The purpose of the utility model is to solve the above-mentioned problems existing in the prior art, and provides a mechanical experiment demonstration device. The utility model adopts a matching structure of a support seat, an angle measuring disc, and a force measurement display component, which effectively solves the technical problems of mechanical experiment demonstration being not intuitive enough and cumbersome to operate in the process of physics teaching, so that students can intuitively explore and understand complex problems of dynamic balance of concurrent forces, thereby promoting the improvement of teaching quality.

[0006] In order to achieve the above purpose, the technical solution adopted by the utility model is as follows:

[0007] The mechanical experiment demonstration device described in the utility model comprises a support seat, an angle measuring disc and a force measuring display component, wherein the angle measuring disc is fixed on the upper part of the support seat, and the force measuring display component is arranged on the support seat and the angle measuring disc; the force measuring display component comprises a display, a first tension sensor, a second tension sensor, a thin rope and a hook weight, the display is fixed on the angle measuring disc, and is electrically connected to the first tension sensor and the second tension sensor respectively, the first tension sensor and the second tension sensor are respectively connected to the upper two sides of the support seat, and the positions of the first tension sensor and the second tension sensor on the support seat are adjustable, the two ends of the thin rope are respectively fixed on the first tension sensor and the second tension sensor, the hook weight is hung on the thin rope, and the first tension sensor, the second tension sensor, the thin rope and the hook weight form a concurrent force dynamic balance demonstration model through the support seat.

[0008] The support seat includes a bottom plate and an inverted U-shaped frame, the lower end of the inverted U-shaped frame is fixedly connected to the bottom plate, and the angle measuring disk is fixed on the upper inner side of the inverted U-shaped frame and is concentric and has the same diameter as the arc portion of the inverted U-shaped frame.

[0009] A rope loop is fixed at the midpoint of the thin rope, and the hook is hung on the rope loop.

[0010] The support seat is also provided with a vertical rod that cooperates with the second tension sensor. The horizontal position of the vertical rod is adjustable, and the position of the second tension sensor on the vertical rod is adjustable. The first tension sensor, the second tension sensor, the thin rope, the vertical rod and the hook cooperate with each other to form a clothesline mechanics demonstration model.

[0011] A horizontal support rod is fixed in the middle of the inverted U-shaped frame. The horizontal support rod has an extension section that exceeds the inverted U-shaped frame. Corresponding slots are provided on the bottom plate and the extension section. The vertical rod is vertically arranged through the slot.

[0012] The vertical rod can be adjusted in position by moving horizontally in the slot.

[0013] The vertical rod is vertically provided with a slide groove, and the second tension sensor moves up and down on the vertical rod through the slide groove to achieve position adjustment, and can be fixed on the vertical rod by a fastener.

[0014] The advantages of adopting the utility model are:

[0015] 1. The mechanical experiment demonstration device of the utility model firstly adopts the matching structure of the support seat, the angle measuring disc and the force measuring display assembly, and is applied to teaching activities, so that the demonstration process is intuitive and clear, and the operation is simple and easy, which helps students overcome the comprehension obstacles of the problem of dynamic balance of concurrent forces, and further helps students deeply understand the principles and laws of dynamic balance of concurrent forces.

[0016] Secondly, the device displays accurate tension data in real time through the electrical connection between the display and the tension sensor, ensuring the real-time and intuitive nature of the experiment. At the same time, the display is fixed on the angle scale disk and works in conjunction with the tension sensor, which can effectively reduce human reading errors and significantly improve experimental accuracy.

[0017] Thirdly, the positions of the first tension sensor and the second tension sensor on the support base are adjustable, which provides a convenient operation experience for the experimenter. The experimenter can easily adjust the positions of the first tension sensor and the second tension sensor according to the experimental requirements, thereby simulating the change of tension of the thin rope on the hook at different angles. This makes the experimental process more flexible and can be demonstrated and verified repeatedly.

[0018] In addition, the coordinated structure of the support base, angle measuring disc and force measuring display assembly is used to conduct intuitive mechanical experiment demonstrations, which enriches the teaching methods, injects new vitality into physics teaching and promotes the improvement of teaching quality.

[0019] In summary, the mechanical experiment demonstration device of the utility model adopts the matching structure of the support seat, the angle measuring disc and the force measuring display assembly, which is beneficial to the intuitiveness of the mechanical experiment demonstration in physics teaching and the simplicity of the operation process. This structural design not only meets the intuitive teaching, but also helps students overcome the understanding obstacles of the dynamic balance problem of concurrent forces, thereby significantly improving the quality of physics teaching.

[0020] 2. The mechanical experiment demonstration device of the utility model adopts a fixed connection structure of the bottom plate and the inverted U-shaped frame to ensure the stability of the device; in addition, the angle measuring disc matches the arc portion of the inverted U-shaped frame, providing an accurate reference for measuring the angle and ensuring the accuracy of the experiment.

[0021] 3. The mechanical experiment demonstration device of the utility model fixes the rope loop at the midpoint of the thin rope and hangs the hook on the rope loop, thereby ensuring that the hook does not slide on the thin rope, ensuring that the experimental conditions are met, and enhancing the stability and operability of the concurrent force dynamic balance experiment demonstration.

[0022] 4. The mechanical experiment demonstration device of the utility model adopts a design in which the horizontal position of the vertical rod is adjustable, and the position of the second tension sensor on the vertical rod is adjustable, so that the device can more realistically simulate the change of the tension of the hook at different positions and angles of the actual clothesline, thereby helping students to understand the principles of clothesline mechanics more comprehensively and enhancing the intuitiveness of the experimental demonstration of the device.

[0023] 5. The mechanical experiment demonstration device of the utility model, through the slot design on the horizontal support rod and the bottom plate, allows the vertical rod to move stably horizontally in the slot through the guiding effect of the slot. Firstly, the stability of the device is enhanced, and secondly, it meets the requirements of the clothesline mechanics experiment demonstration. When the vertical rod is adjusted to different positions through horizontal movement, the experimenter can intuitively observe the change of the tension of the thin rope on the hook, so as to better understand the concept of clothesline mechanics and its application in practical problems.

[0024] 6. The mechanical experiment demonstration device of the utility model, through the slide groove design on the vertical rod, the second tension sensor can move up and down along the slide groove, thereby driving the position of the thin rope to change; the second tension sensor is limited and fixed by fasteners, ensuring the stability of the position of the second tension sensor and the thin rope during the experiment. This design allows the experimenter to intuitively observe whether the tension on the hook changes when the thin rope is at different positions on the vertical rod, thereby effectively demonstrating and verifying the relevant clothesline mechanical principles, and further enhancing the intuitiveness of the demonstration of the device experiment. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the structure of the utility model;

[0026] Figure 2 It is a force diagram of the parallelogram rule of the utility model;

[0027] Figure 3 It is a structural schematic diagram of the mechanical demonstration model of the clothes drying rod of the utility model;

[0028] Figure 4 It is a force diagram of the mechanical demonstration model of the clothes drying rod of the utility model.

[0029] The numbers in the figure are: 1. inverted U-shaped frame, 2. thin rope, 3. angle measuring disk, 4. rope loop, 5. display, 6. first tension sensor, 7. second tension sensor, 8. bottom plate, 9. horizontal support rod, 10. vertical rod, 11. hook weight. DETAILED DESCRIPTION

[0030] The following will be described in detail in conjunction with the drawings and specific implementation methods of the specification. In the present utility model, for the convenience of description, the description of the relative position relationship of each component is described according to the layout of the drawings in the specification, such as: the position relationship of front, back, top, bottom, left, right, etc. is determined according to the layout direction of the drawings in the specification.

[0031] A mechanical experiment demonstration device, such as Figure 1 As shown, it includes a support base, an angle measuring disc 3 and a force measuring display assembly. The angle measuring disc 3 is fixed on the upper part of the support base, and the force measuring display assembly is arranged on the support base and the angle measuring disc 3.

[0032] Further, the force measurement and display assembly includes a display 5, a first tension sensor 6, a second tension sensor 7, a thin rope 2 and a hook 11. The display 5 is fixed on the angle measuring disc 3 and is electrically connected to the first tension sensor 6 and the second tension sensor 7 respectively. The first tension sensor 6 and the second tension sensor 7 are respectively connected to the upper sides of the support seat, and the positions of the first tension sensor 6 and the second tension sensor 7 on the support seat are adjustable. The first tension sensor 6 and the second tension sensor 7 are also respectively equipped with hooks, through which the two ends of the thin rope 2 are respectively fixed to the first tension sensor 6 and the second tension sensor 7, and the hook 11 is hung on the thin rope 2. The aforementioned thin rope 2 is a complete thin rope. In the experimental demonstration operation, the thin rope 2 can also be formed by connecting two equal lengths of thin ropes by knotting. When the thin ropes are straightened, the knot point of the two thin ropes is the midpoint of the thin rope 2, and this midpoint must be concentric with the angle measuring disc 3.

[0033] A mainboard is also fixed to the back of the display 5. After receiving the signals from the first tension sensor 6 and the second tension sensor 7, the mainboard performs a series of processing and conversion, and finally outputs the tension signal to the display 5. The display 5 can show the tension values ​​of the two ends of the string 2 to the hook code 11 to the experimenter in the form of numerical values. It should be noted that the connection method between the first tension sensor 6 and the second tension sensor 7 and the mainboard can be wired or wireless, and the signal connection method is a technology known to technicians in the field; in addition, the method for the mainboard to receive the signal of the tension sensor for data processing and conversion is also a technology known to technicians in the field, and will not be repeated here.

[0034] Thus, the first tension sensor 6, the second tension sensor 7, the thin rope 2 and the hook 11 form a concurrent force dynamic balance demonstration model through the support base.

[0035] Embodiment 1:

[0036] In this embodiment, Figure 1As shown, the support seat includes a bottom plate 8 and an inverted U-shaped frame 1, and the lower end of the inverted U-shaped frame 1 is fixedly connected to the bottom plate 8, which can enhance the stability of the support seat. The angle measuring disc 3 is fixed on the inner side of the upper part of the inverted U-shaped frame 1, and is concentric and diametric with the arc portion of the inverted U-shaped frame 1. It should be noted that in this embodiment, the positions of the first tension sensor 6 and the second tension sensor 7 on the support seat are adjustable, that is, the first tension sensor 6 is located on the arc edge of the inverted U-shaped frame 1, and takes the highest point of the inverted U-shaped frame 1 as the starting point, and it can be moved within the range of 90 degrees in the counterclockwise direction for position adjustment; similarly, the second tension sensor 7 is located on the arc edge of the inverted U-shaped frame 1, and also takes the highest point of the inverted U-shaped frame 1 as the starting point, and moves within the range of 90 degrees on the arc edge of the inverted U-shaped frame 1 in the clockwise direction for position adjustment. Through this mobile position adjustment method, the position of the string 2 can be changed to meet the different needs of the experiment. When the first tension sensor 6 and the second tension sensor 7 are moved to the positions required for the experiment, they can be fixed at the designated positions by means of buckles, fixing pins or clamps, etc. In this way, the experimenter can visually observe the change of the tension of the two ends of the string 2 on the hook 11 on the display 5.

[0037] An angle scale is also drawn on the angle measuring disc 3, which is convenient for directly reading the angle data between the thin rope 2 and the vertical direction during the experimental demonstration. Therefore, the angle measuring disc 3 cooperates with the force measurement display component to facilitate the experimenter to demonstrate the dynamic balance of concurrent forces and verify and analyze experimental data. This design not only significantly improves the accuracy and reliability of the experiment, but also greatly simplifies the experimental operation, enhances the intuitiveness of the experimental demonstration, and helps to deeply understand the principles and laws of the dynamic balance of concurrent forces, thereby improving the quality of physics teaching.

[0038] In order to more clearly illustrate the demonstration method of the mechanical experiment demonstration device of the utility model in the experiment of the dynamic balance problem of concurrent forces, the whole demonstration process will be explained as follows.

[0039] Experiment 1: Demonstrate and verify the dynamic balance of three forces.

[0040] Three-force dynamic balance means that when an object is in equilibrium under the action of three non-parallel forces, the three forces must be coplanar and co-pointed, and the resultant force is zero. Three coplanar non-parallel forces that are in balance must converge at one point, and the resultant force of any two forces is equal to the third force in magnitude and opposite in direction.

[0041] During the experimental demonstration, Figure 1 As shown, the steps are as follows:

[0042] Step 1: In the preparation stage, a loop 4 is fixed at the midpoint of the string 2, so that the loop 4 intersects with the midpoint of the string 2 to form a node O. In this way, the string 2 is divided into two sections by the loop 4, and the length of each section is equal to the radius of the angle measuring disc 3, and in the stretched state, the node O is ensured to be concentric with the angle measuring disc 3.

[0043] Step 2: Draw a dotted line on the angle measuring disc 3 through its center and in the vertical direction. During the experimental demonstration, starting from the drawn dotted line, the movable adjustment range of the first tension sensor 6 is limited to the interval of 90 degrees counterclockwise along the arc edge of the inverted U-shaped frame 1, while the movable adjustment range of the second tension sensor 7 is limited to the interval of 90 degrees clockwise along the arc edge of the inverted U-shaped frame 1. The two sections of the string change their positions driven by the first tension sensor 6 and the second tension sensor 7, while the node O always coincides with the center of the angle measuring disc 3, so that the experimenter can read the angle between the two sections of the string in the vertical direction.

[0044] Step 3: According to the movable adjustment range described in step 2, and by means of buckles, fixing pins or clamps, the first tension sensor 6 and the second tension sensor 7 are respectively fixed at the required experimental positions of the arc edge of the inverted U-shaped frame 1.

[0045] Step 4: Hang the hook weight 11 of known mass on the rope loop 4 and keep it still. In this case, the two ends of the thin rope 2 will apply tension to the hook weight 11, which are recorded as tension F1 and tension F2 respectively. At the same time, the first tension sensor 6 and the second tension sensor 7 detect the two tensions respectively and convert the tensions into electrical signals. Subsequently, the electrical signals are processed by the main board, and the values ​​of tension F1 and tension F2 are intuitively displayed on the display 5.

[0046] Step 5: The experimenter can also paste a circular paper with the same center and radius as the angle measuring disk 3 on the angle measuring disk 3. This paper is also marked with angle scales and has a dotted line drawn on it that completely overlaps with the dotted line drawn on the angle measuring disk 3, so that the experimenter can directly draw a force diagram on the paper and perform force analysis.

[0047] Step 6: According to steps 1-5, the experimenter adjusts the positions of the first tension sensor 6 and the second tension sensor 7 multiple times within the movable adjustment range of the arc edge of the inverted U-shaped frame 1 to change the positions of the two thin ropes. At the same time, the experimenter uses the angle measuring disc 3 to observe the change in the vertical angle of the two thin ropes. Through the intuitive display of the display 5, the three-force dynamic balance of the two thin ropes in different positions can be verified multiple times. It should be noted that the tension of the hook 11 on the thin rope 2 is a constant force among the three forces. When the direction of another force or two forces changes, the law of its size change can be displayed through the display 5.

[0048] In addition, in order to study the dynamic balance law of the three forces when the angle between the tensions F1 and F2 remains unchanged, the experimenter needs to ensure that the straight-line distance between the first tension sensor 6 and the second tension sensor 7 is always equal when moving them. The experimenter can use a straight rod to measure this distance and keep this distance unchanged during each movement, thereby realizing the study under the dynamic balance condition of the three forces.

[0049] Experiment 2: Demonstrate and verify the parallelogram law of forces.

[0050] The composition of forces follows the parallelogram law. Figure 2 As shown, if a parallelogram is constructed with line segments representing two concurrent forces F1 and F2 as adjacent sides, then the magnitude and direction of the resultant force F can be expressed by the diagonal line between the two adjacent sides.

[0051] This experiment will continue to combine Figure 1 Instructions, the steps are as follows:

[0052] Step 1: Follow the operating methods in steps 1-4 of Experiment 1 and record the exact values ​​and directions of the pulling forces F1 and F2 on the display 5.

[0053] Step 2: The experimenter can also stick a circular paper with the same center and radius as the angle measuring disk 3 on the angle measuring disk 3. This paper is also marked with angle scales and has a dotted line drawn on it that completely overlaps with the dotted line drawn on the angle measuring disk 3, so that the experimenter can directly draw the following on the paper: Figure 2 The force diagram is shown.

[0054] Step 3: Make sure the hook weight 11 of known mass is at rest, read the angles between the two thin ropes and the dotted line, and record them as θ1 and θ2, respectively, and then use the force diagram to analyze and record the magnitude of the resultant force F. Figure 2 As shown, the diagonal line between the tensions F1 and F2 represents their resultant force F. Since the analysis process of the resultant force F value belongs to the scope of high school physics knowledge points, it will not be repeated here.

[0055] Step 4: Next, fix any tension sensor to the top of the inverted U-shaped frame 1, and fix one end of the string 2 to the tension sensor at the top of the inverted U-shaped frame 1 along the direction of the dotted line drawn on the angle measurement disk 3, and hang the hook 11 of the same mass known in the previous step on the other end. For the accuracy of the experimental demonstration, at this time, it is necessary to ensure that the string 2 coincides with the drawn dotted line, and at the same time, observe the display 5 and record the exact value of the tension F' of the string 2 on the hook 11 at this time.

[0056] Step 5: Compare the recorded tension F´ and resultant force F, and intuitively conclude that the magnitude of resultant force F is infinitely close to or even equal to the tension F´, and is within the acceptable error range of the experiment.

[0057] In order to enhance the reliability of experimental demonstration and verification, the above steps can be repeated multiple times to observe whether the results are consistent.

[0058] Steps 1-5 in this experiment, through specific demonstration and verification, show that the magnitude and direction of the resultant force F of the two concurrent forces F1 and F2 are indeed equivalent to the diagonal of the parallelogram formed by the line segments of the two concurrent forces F1 and F2 as adjacent sides. This experimental result confirms that when dealing with the problem of the synthesis of two concurrent forces, the parallelogram rule can be used to solve their resultant force. By drawing a dotted line on the angle measuring disk 3, and using the thin rope 2 and the tension sensor, a mechanical experiment demonstration device with intuitive demonstration and simple operation is provided for students, so that students can deeply understand and skillfully use the parallelogram rule to calculate the resultant force of concurrent forces. Compared with the traditional spring balance force measurement method, the mechanical experiment demonstration device of the utility model can record parameters through the display in a static state, thereby greatly reducing the error caused by human readings and significantly improving the accuracy and reliability of the experiment.

[0059] Embodiment 2:

[0060] like Figure 3 As shown, a vertical rod 10 cooperating with the second tension sensor 7 is also provided on the support seat, the horizontal position of the vertical rod 10 is adjustable, and the position of the second tension sensor 7 on the vertical rod 10 is also adjustable. It should be noted that the difference between this embodiment and embodiment 1 is that the second tension sensor 7 has no connection relationship with the inverted U-shaped frame 1, and is only connected to the vertical rod 10. The first tension sensor 6, the second tension sensor 7, the thin rope 2, the vertical rod 10 and the hook 11 cooperate with each other to form a clothes drying rod mechanics demonstration model, and then through the tension value displayed in real time by the display 5, the tension change of the hook 11 at different positions and angles of the actual clothes drying rod can be intuitively seen. The experimenter can adjust the state of the model as needed to conduct experiments under different conditions.

[0061] In order to simulate the scene of hanging clothes on a clothesline in real life and demonstrate and verify the mechanical principles and laws of the clothesline, the hook weight 11 in this embodiment is directly hung on the thin rope 2 and can slide freely and smoothly on the thin rope 2, which is different from the method of using the rope loop 4 for fixed hanging in Example 1. If the simple hanging method is not enough to meet the experimental conditions, a smooth hook can be used to firmly hang the hook weight 11 on the smooth hook to ensure the smooth progress of the experiment.

[0062] Specifically, a horizontal support rod 9 is fixed in the middle of the inverted U-shaped frame 1. Figure 3 Taking the direction shown as an example, the horizontal support rod 9 has an extension section that exceeds the inverted U-shaped frame 1 to the right, and corresponding slots are provided on the bottom plate 8 and the extension section. The vertical rod 10 is vertically arranged through the slot, and can be adjusted in position by horizontally moving in the slot. In order to enhance the experimental effect of the left and right movement of the vertical rod 10, the length of its extension section can be appropriately extended within the scope of satisfying the actual operability to enhance the observability of the experiment. In addition, when the vertical rod 10 is horizontally moved for position adjustment, if the gravity of the hook weight 11 is not enough to overcome the resistance generated by the slot to the vertical rod 10, the vertical rod 10 will remain stable and will not tilt in the slot. However, when the gravity of the hook weight 11 exceeds the resistance of the slot to the vertical rod 10, in order to maintain the stability of the vertical rod 10 and prevent it from tilting, a fastener can be used to limit and fix the vertical rod 10, thereby ensuring the accuracy and smooth progress of the experimental demonstration. The fastener can be an existing component such as a clamp or a fixture.

[0063] Furthermore, a slide groove is vertically arranged on the vertical rod 10, and the second tension sensor 7 is moved up and down on the vertical rod 10 through the slide groove to achieve position adjustment, and the second tension sensor 7 can be limited and fixed at any stop position required for the experiment on the vertical rod 10 by fasteners, and the fasteners can still be existing components such as the aforementioned clamps or clamps.

[0064] It should be emphasized that in order to reduce the error of the experiment, the second tension sensor 7 (taking a cylindrical tension sensor as an example) in this embodiment must be able to flexibly adjust the vertical angle in the slide slot of the vertical rod 10. Since the connection method of the tension sensor in the slide slot belongs to the known technology of the technicians in the field, it will not be repeated here. This ensures that when the string 2 moves up and down to adjust the position or the vertical rod 10 moves horizontally to adjust the position, the extension line of the string 2 and the axis of the tension sensor 7 always remain coincident.

[0065] The traditional teaching method for the mechanical principles and laws of clothes-drying rods is to draw a force analysis diagram of the clothes-drying rod model, analyze and calculate the changes in the tension of the thin rope when it is hung in different positions, and summarize the conclusions, namely:

[0066] Conclusion 1. When the suspension point is moved up and down, the pole distance, angle and tension remain unchanged;

[0067] Conclusion 2: When moving the pole left or right, the farther the pole is from each other, the smaller the angle becomes and the greater the pulling force; the closer the pole is from each other, the larger the angle becomes and the smaller the pulling force.

[0068] The demonstration and verification experiments in this embodiment can more intuitively confirm that the change in the tension of the thin rope 2 is only related to the pole distance. Figure 3-4As shown, the first tension sensor 6 and the second tension sensor 7 are respectively fixed at the required positions of the experiment on the inverted U-shaped frame 1 and the vertical rod 10 by fasteners, and the distance between the first tension sensor 6 and the second tension sensor 7 is recorded as the rod distance d; then the hook 11 of known mass is hung on the thin rope 2, at this time, the angle of the thin rope 2 in the horizontal direction is recorded as the angle α; the tensions at both ends of the thin rope 2 on the hook 11 are recorded as F1 and F2 respectively; the rope length of the thin rope 2 is L; the gravity of the hook 11 is recorded as gravity G.

[0069] Experiment 3: Demonstrate and verify the clothesline mechanics demonstration model.

[0070] The following demonstration experiment will illustrate how to use the clothes drying rod mechanics demonstration structure. The specific demonstration method is as follows:

[0071] Demonstration method 1: Move and adjust the limit fixed suspension points of the first tension sensor 6 and the second tension sensor 7 up and down at will. At this time, the rod distance d and the angle α remain unchanged, and the display 5 can intuitively show that the tensions F1 and F2 received by the hook 11 remain unchanged.

[0072] Demonstration method 2: Figure 3 Taking the direction shown as an example, the vertical rod 10 is moved to the right, the rod distance d becomes larger, L remains unchanged, the hook weight G remains unchanged, and the angle α becomes smaller. It can be intuitively seen through the display 5 that the tension F1 and F2 of the thin rope 2 become larger.

[0073] Demonstration method 3: Figure 3 Taking the direction shown as an example, the vertical rod 10 is moved to the left, the rod distance d becomes smaller, L remains unchanged, the hook weight G remains unchanged, and the angle α becomes larger. It can be intuitively seen through the display 5 that the tension F1 and F2 of the thin rope 2 become smaller.

[0074] It should be noted that in the clothesline mechanics demonstration model demonstration experiment, the tension F1 and F2 at both ends of the thin rope 2 are equal.

[0075] In summary, by applying the coordinated structure of the support seat, angle measuring disc and force display assembly to teaching activities, students can intuitively explore and understand the problem of dynamic equilibrium of concurrent forces. This design is intuitive and easy to understand, easy to operate, and can effectively help students overcome the difficulty of understanding the principle of dynamic equilibrium of concurrent forces, enrich teaching methods, and further promote the improvement of physics teaching quality.

[0076] The above description is only a specific implementation method of the present utility model. Any feature disclosed in this specification, unless otherwise stated, can be replaced by other equivalent or alternative features with similar purposes; all disclosed features, or all methods or steps in the process, except for mutually exclusive features and / or steps, can be combined in any way.

Claims

1. A mechanical experiment demonstration device, characterized in that: It comprises a support seat, an angle measuring disc (3) and a force measuring display assembly, wherein the angle measuring disc (3) is fixed on the upper part of the support seat, and the force measuring display assembly is arranged on the support seat and the angle measuring disc (3); The force measurement and display assembly comprises a display (5), a first tension sensor (6), a second tension sensor (7), a thin rope (2) and a hook weight (11); the display (5) is fixed on the angle measuring disc (3) and is electrically connected to the first tension sensor (6) and the second tension sensor (7) respectively; the first tension sensor (6) and the second tension sensor (7) are respectively connected to the upper two sides of a support seat, and the positions of the first tension sensor (6) and the second tension sensor (7) on the support seat are adjustable; the two ends of the thin rope (2) are respectively fixed on the first tension sensor (6) and the second tension sensor (7); the hook weight (11) is hung on the thin rope (2); the first tension sensor (6), the second tension sensor (7), the thin rope (2) and the hook weight (11) form a concurrent force dynamic balance demonstration model through the support seat.

2. The mechanical experiment demonstration device according to claim 1, characterized in that: The support seat comprises a bottom plate (8) and an inverted U-shaped frame (1), the lower end of the inverted U-shaped frame (1) being fixedly connected to the bottom plate (8), and the angle measuring disc (3) being fixed to the inner side of the upper part of the inverted U-shaped frame (1) and being concentric and having the same diameter as the arc-shaped part of the inverted U-shaped frame (1).

3. The mechanical experiment demonstration device according to claim 2, characterized in that: A rope loop (4) is fixed at the midpoint of the thin rope (2), and the hook (11) is hung on the rope loop (4).

4. The mechanical experiment demonstration device according to claim 2, characterized in that: The support seat is also provided with a vertical rod (10) cooperating with the second tension sensor (7); the horizontal position of the vertical rod (10) is adjustable; the position of the second tension sensor (7) on the vertical rod (10) is adjustable; the first tension sensor (6), the second tension sensor (7), the thin rope (2), the vertical rod (10) and the hook (11) cooperate with each other to form a clothes-drying rod mechanics demonstration model.

5. The mechanical experiment demonstration device according to claim 4, characterized in that: A transverse support rod (9) is fixed at the middle position of the inverted U-shaped frame (1), the transverse support rod (9) has an extension section extending beyond the inverted U-shaped frame (1), the bottom plate (8) and the extension section are both provided with corresponding slots, and the vertical rod (10) is vertically arranged through the slots.

6. The mechanical experiment demonstration device according to claim 5, characterized in that: The vertical rod (10) can be adjusted in position by moving horizontally in the slot.

7. The mechanical experiment demonstration device according to claim 6, characterized in that: The vertical rod (10) is provided with a slide groove in the vertical direction, and the second tension sensor (7) can be moved up and down on the vertical rod (10) through the slide groove to achieve position adjustment, and can be fixed on the vertical rod (10) by a fastener.

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