Double-pendulum motion demonstration instrument

Abstract

The utility model discloses a double pendulum motion demonstration instrument, comprising a support frame; the pair of fixed seats is arranged at the upper part of the support frame; the upper ends of the pair of swing rod structures are rotationally connected with the pair of fixed seats respectively; the pair of swing rod driving structures is used for driving the pair of swing rod structures to swing relative to the pair of fixed seats respectively; each oscillating bar structure comprises an oscillating bar of which the upper part is rotationally connected with the corresponding fixed seat; a plurality of pendulum balls with different masses or the same mass are detachably mounted on the pendulum rod; each swing rod driving structure comprises a magnetic field generating assembly fixedly installed on the corresponding fixing base. And the magnet is fixedly arranged at the upper part of the swing rod and can drive the swing rod to swing relative to the fixed seat under the action of the magnetic field generated by the magnetic field generating assembly. According to the demonstration instrument, the double pendulums are adopted to more intuitively carry out a parameter comparison experiment of the influence of the pendulum length on the period for students, the pendulum length, the pendulum ball quality and the pendulum amplitude of the double pendulums can be adjusted, the demonstration effect is good, the demonstration instrument is easily observed and understood by the students, and the intuition and the effect of the experiment are enhanced.

Description

Technical Field

[0001] This utility model relates to the field of teaching aids technology, and in particular to a double pendulum motion demonstrator for teaching demonstrations. Background Technology

[0002] In middle school physics teaching, the simple pendulum motion is one of the most basic forms of motion. In this part of the classroom teaching, teachers often use on-site demonstrations to explain to students the influence of the pendulum length on the period of the simple pendulum.

[0003] Existing pendulum motion demonstration teaching aids generally include a pendulum bob, a string or rod suspending the pendulum bob, and a connector attached to the top of the string or rod to fix it in place. While these pendulum demonstration teaching aids have a simple structure, they suffer from the following shortcomings:

[0004] (1) Inconvenient adjustment and limited demonstration effect: The distance between the pendulum ball and the silk thread or the top of the rod is fixed, so the pendulum length, pendulum ball mass and swing amplitude cannot be flexibly adjusted, which limits the scope of experimental demonstration.

[0005] (2) Insufficient stability: Although the above teaching aids have a simple structure, the pendulum is easily affected by external interference (such as vibration or wind) during the swing process, which may lead to less than ideal demonstration results. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides a double pendulum motion demonstrator. It has a simple structure and is easy to use and carry. Using a double pendulum allows students to conduct a more intuitive comparative experiment on the effect of pendulum length on period. The pendulum length, pendulum bob mass, and swing amplitude of the two pendulums can be adjusted as needed. Moreover, it is not affected by the external environment during the swing process, resulting in a better demonstration effect. It is easier for students to observe and understand, thus enhancing the intuitiveness of the experiment and the teaching effect.

[0007] To achieve the above-mentioned objectives of this utility model, a double pendulum motion demonstrator is provided, comprising: a support frame; a pair of fixed seats mounted on the upper part of the support frame; a pair of pendulum rod structures whose upper ends are respectively rotatably connected to the pair of fixed seats; and a pair of pendulum rod driving structures for driving the pair of pendulum rod structures to swing relative to the pair of fixed seats; wherein each pendulum rod structure includes: a pendulum rod whose upper part is rotatably connected to the corresponding fixed seat; and multiple pendulum balls of different or identical masses detachably mounted on the pendulum rod; wherein each pendulum rod driving structure includes: a magnetic field generating component fixedly mounted on the corresponding fixed seat; and a magnet fixedly mounted on the upper part of the pendulum rod, which can drive the pendulum rod to swing relative to the fixed seat under the action of the magnetic field generated by the magnetic field generating component.

[0008] Preferably, the pendulum structure further includes a connecting sleeve mounted on the pendulum, and the pendulum ball can be placed inside the connecting sleeve.

[0009] Preferably, the magnetic field generating assembly includes a coil mounted on a fixed base and a power supply mounted on the fixed base and electrically connected to the coil.

[0010] Preferably, the connecting sleeve is a sleeve-shaped connecting sleeve, which is fixedly installed on the clamping clamp, and the clamping clamp can clamp onto the swing arm.

[0011] Preferably, the support frame or the fixed base is equipped with hooks for easy hanging.

[0012] Preferably, the bottom of the support frame is a horizontal base that facilitates its placement on a horizontal object.

[0013] Compared with the prior art, the double pendulum motion demonstrator of this utility model has the following advantages:

[0014] This utility model of a double pendulum motion demonstrator has a simple structure, is easy to use and carry, and has a low cost. Using a double pendulum allows students to conduct a more intuitive comparative experiment on the effect of pendulum length on period. The pendulum length, pendulum bob mass, and swing amplitude of the two pendulums can be adjusted as needed. Moreover, it is not affected by the external environment during the swing process, resulting in a better demonstration effect, making it easier for students to observe and understand, and enhancing the intuitiveness of the experiment and the teaching effect.

[0015] The present invention will now be described in detail with reference to the accompanying drawings. Attached Figure Description

[0016] Figure 1 This is a front view of the first structure of the double pendulum motion demonstrator of this utility model;

[0017] Figure 2 This is a left view of the first structure of the double pendulum motion demonstrator of this utility model;

[0018] Figure 3 This is a perspective view of the first structure of the double pendulum motion demonstrator of this utility model;

[0019] Figure 4 This is a left view of the second structure of the double pendulum motion demonstrator of this utility model;

[0020] Figure 5 This is a front view of the third structure of the double pendulum motion demonstrator of this utility model;

[0021] Figure 6 This is a front view of the fourth structure of the double pendulum motion demonstrator of this utility model;

[0022] Figure 7 This is a schematic diagram of the second type of connecting sleeve of this utility model;

[0023] Figure 8 This is a schematic diagram of the third type of connecting sleeve of this utility model. Detailed Implementation

[0024] like Figures 1-6 The figures show schematic diagrams of four different structures of the double pendulum motion demonstrator of this utility model. As can be seen from the figures, the double pendulum motion demonstrator of this utility model includes: a support frame 5; a pair of fixed seats 2 installed on the upper part of the support frame; a pair of pendulum rod structures whose upper ends are rotatably connected to the pair of fixed seats respectively; a pair of pendulum rod driving structures for driving the pair of pendulum rod structures to swing relative to the pair of fixed seats respectively; wherein, each pendulum rod structure includes: a pendulum rod 7 whose upper part is rotatably connected to the corresponding fixed seat; multiple pendulum balls of different or the same mass (not shown in the figure) detachably installed on the pendulum rod; wherein, each pendulum rod driving structure includes: a magnetic field generating component fixedly installed on the corresponding fixed seat; a magnet 9 fixedly installed on the upper part of the pendulum rod, which can drive the pendulum rod to swing relative to the fixed seat under the action of the magnetic field generated by the magnetic field generating component.

[0025] Specifically, the support frame of this utility model is a frame structure, consisting of two vertical columns, a crossbeam connecting the tops of the columns, and a horizontal base 8 connecting the bottoms of the columns, forming a stable support frame. During manufacturing, the support frame can be made of wood, plastic, or other materials. The horizontal base is connected to the lower ends of the columns by screws, glue, plug-in connections, or bolts. The crossbeam is connected to the tops of the columns by screws, glue, or threads. The horizontal base at the bottom of the support frame facilitates stable placement of the support frame on a horizontal surface when teachers demonstrate pendulum experiments to students.

[0026] This utility model features a pair of fixed seats fixedly installed on the upper part of a support frame by means of bolts or adhesive. The lower parts of the pair of fixed seats are rotatably connected to a pair of swing rod structures. The fixed seats can be frame structures, with a mounting cavity opened in the lower part of the fixed seats. A cover (not shown in the figure) is provided at the mounting cavity and is detachably connected to the mounting cavity (such as by a snap-fit ​​structure of the prior art) to close the mounting cavity.

[0027] The pair of pendulum structures are identical in structure, each including: a pendulum rod 7 rotatably connected to the corresponding fixed seat at its upper part; and multiple pendulum balls (not shown in the figure) of different or identical masses detachably mounted on the pendulum rod. During manufacturing, the pendulum rods can be made of metal, and the pair of pendulum rods are of the same length and are suspended parallel to each other on the crossbeam of the support frame at certain intervals.

[0028] To allow the pendulum to rotate relative to the fixed base and swing freely in the vertical plane, a through hole extending vertically can be made in the lower part of the fixed base, through which the pendulum passes from bottom to top. A pin (not shown in the figure) is placed at the through hole of the pendulum passing through the through hole to rotatably connect the pendulum to the fixed base. Correspondingly, a corresponding through hole or countersunk hole can be made at the through-pin location of the fixed base to allow the pin to be inserted. In this way, when an external force is applied, the pendulum can swing relative to the fixed base like a pendulum.

[0029] During the design process, multiple through holes can be spaced along the length of the upper end of the pendulum rod. Depending on the required pendulum rod length for the experiment, these through holes at different locations can be inserted through the through holes in the fixed base, and the pendulum rod can be hinged to the fixed base using pins inserted into these through holes. Connecting the pendulum rod to the fixed base using pins is based on existing technology and will not be detailed here. Alternatively, bearings can be installed in the through holes of the fixed base, with the top of the pendulum rod passing through the bearing for rotatable connection to the fixed base. Of course, other existing structures can also be used to rotatably connect the pendulum rod to the fixed base.

[0030] Alternatively, a connecting rod can be bolted to the top of the pendulum. A countersunk hole or through hole extending vertically is made in the lower part of the fixed base. The upper part of the connecting rod is inserted into the countersunk hole or through hole and hinged to the fixed base by a pin, while the lower part extends out of the bottom of the fixed base. During the experiment, the tops of pendulums of different lengths can be bolted together with the connecting rod as needed.

[0031] Furthermore, the pendulum can also be telescopic, allowing for length adjustment according to experimental needs. The telescopic pendulum can utilize existing modular structures, etc.

[0032] To facilitate monitoring of the swing angle of the pendulum relative to the fixed seat, an angle scale with different angles marked with the center of the through hole or countersunk hole as the center can be installed on the outer wall of the fixed seat.

[0033] To increase the inertia of the pendulum's swing, multiple pendulum balls of different or identical masses are placed on the pendulum, allowing for replacement of different pendulum balls as needed for experimental demonstrations.

[0034] During the design process, a connecting sleeve 6 can be installed on the pendulum rod, with the pendulum ball secured inside the connecting sleeve. Pendulum balls of different masses can be made of different materials but with the same diameter, such as pendulum balls made of different materials like metal or wood. Correspondingly, a sleeve-shaped connecting sleeve (e.g., ...) can be used. Figure 1 As shown), its back is fixed to the pendulum rod by screws or adhesive, and a pendulum ball with a diameter equivalent to the inner diameter of the connecting sleeve can be placed inside the connecting sleeve. Alternatively, pendulum balls of different masses can be made of the same or different materials but with different diameters, and correspondingly, the connecting sleeve adopts a design as shown in the image. Figure 7 , Figure 8 The structure shown includes a sleeve-shaped connecting sleeve 61, one or two pairs of elastic members 62 with one end fixedly connected to the inner wall of the connecting sleeve, and an arc-shaped claw 63 fixedly connected to the other end of each elastic member. The arc-shaped claw can grasp pendulum balls of different diameters by extending and retracting the elastic members.

[0035] Furthermore, to allow for changing the position of the pendulum bob on the pendulum rod as needed for experimental demonstrations, the connecting sleeve of this invention can be detachably fixed to the pendulum rod. For example, the back of the aforementioned sleeve-shaped connecting sleeve can be fixedly connected to the handle of a clamping clip, which can then be clamped onto the pendulum rod. The structure of the clamping clip can refer to the existing clamp structure with two hinged clamping rods, and will not be described in detail here.

[0036] To limit the lowest position of the pendulum ball on the pendulum rod, a stop block 10 can also be installed at the lower part of the pendulum rod (see [reference]). Figure 4 The lowest position of the connecting sleeve and the pendulum ball on the pendulum rod is limited by a stop block. In addition, scale marks can be set on the pendulum rod to mark the different positions of the pendulum ball relative to the hinge point between the pendulum rod and the fixed seat.

[0037] In order to ensure that the swing amplitude of the two pendulum rods is consistent during the experiment, making it easier for students to observe and understand, and enhancing the intuitiveness and teaching effect of the experiment, this utility model uses a pair of pendulum rod driving structures to drive a pair of pendulum rod structures to swing relative to a pair of fixed seats. Each pendulum rod driving structure includes: a magnetic field generating component fixedly installed on the corresponding fixed seat; and a magnet 9 fixedly installed on the upper part of the pendulum rod, which can drive the pendulum rod to swing relative to the fixed seat under the action of the magnetic field generated by the magnetic field generating component.

[0038] This utility model's magnetic field generating assembly includes a coil 4 mounted on a fixed base and a power supply 3 mounted on the fixed base and electrically connected to the coil via a wire. Both the coil and the power supply are housed within the mounting cavity of the fixed base, and a cover is fastened to prevent them from falling off. The power supply can be a primary battery (such as an AA battery), a storage battery, or a lithium battery. During assembly, the coil can be fixed in the mounting cavity by adhesive or bolts, with the central axis of the coil parallel to the extension direction of the pendulum rod when it is placed vertically. If a primary battery is used, a battery holder is fixedly placed within the mounting cavity. During use, a switch can be installed on the fixed base to control whether the power supply supplies power to the coil. Furthermore, a control circuit can be installed to control the current magnitude. Correspondingly, appropriate circuit components are installed within the mounting cavity of the fixed base. The control circuit is readily available to those skilled in the art and will not be described in detail here. Alternatively, if a primary battery is used, a switch may not be necessary; the primary battery can simply be placed in the battery holder during the experiment. The battery holder can accommodate different numbers of primary batteries as needed.

[0039] When the coil is energized, it generates a magnetic field, which interacts with the magnetic field generated by the magnet on the pendulum. Since the strength and direction of the magnetic field generated by the energized coil are different at different positions, the magnetic force on different parts of the magnet below the coil is different in magnitude and direction. As a result, the magnet swings left and right around the hinge point with the fixed base under the action of the magnetic force.

[0040] In the design, the structures of a pair of pendulum rods and a pair of pendulum rod drive structures can be completely identical. The pendulum rods can be made of lightweight and high-strength materials, such as aluminum alloy or carbon fiber, to reduce the impact of their own weight on the oscillation. The upper end of the pendulum rod is hinged to the fixed base, while the lower end can swing freely.

[0041] To adapt to different demonstration conditions, the presenter of this utility model can be placed on a horizontal object such as a table, or it can be suspended from an object. Accordingly, hooks 1 for easy hanging can be installed on the support frame or fixed base. In the design, one hook can be installed on each fixed base (e.g., ...). Figure 1 As shown), a hook can also be installed on the support frame (such as...). Figure 5 , Figure 6 As shown), the hook can be a triangular hook (such as...). Figure 1 , Figure 5 As shown), it can also be a lug with a round hole in the middle (such as...). Figure 6 (As shown).

[0042] Furthermore, during manufacturing, the base can be designed with added weight, such as being made of metal, or having counterweights placed on it. In fact, anti-slip pads can be fixed to the bottom of the base by screws or adhesive to ensure the stability of the entire teaching aid during the experiment and reduce the impact of external interference on the experimental results.

[0043] During manufacturing, the dimensions or angles of each part can be determined using the following parameters:

[0044] The adjustable range of the lever length (LL) is 10cm to 100cm, accurate to 1mm.

[0045] Pendulum mass (mm): Pendulums of different masses (e.g., 50g, 100g, 150g) are available to meet diverse experimental needs.

[0046] Initial swing angle (θ0) of the pendulum: adjustable range from 0° to 30°, with an error of less than ±0.5°.

[0047] The following describes the teaching demonstration process of the double pendulum motion demonstrator of this utility model when using AA batteries as a power source.

[0048] Step 1: Assemble the double pendulum motion demonstrator (referred to as the teaching aid).

[0049] Remove all parts of the teaching aid from the packaging and connect them according to the diagram, ensuring the base is stable and the connections between parts are secure. Alternatively, you can assemble the parts beforehand and simply take them out for class.

[0050] Step 2: Adjust the parameters of the double pendulum

[0051] Pendulum length adjustment: According to the experimental requirements, adjust the suspension position of the pendulum or adjust the length of the pendulum itself, and use a scale to measure the effective length of the pendulum to ensure that the length of the pair of pendulums installed on the pair of fixed seats meets the experimental requirements.

[0052] Adjusting the pendulum position: Adjust the position of the connecting sleeve on the pendulum rod to adjust the position of the pendulum ball on the pendulum rod, ensuring that the pendulum ball is fixed inside the connecting sleeve so that the pendulum ball maintains a stable position during movement.

[0053] Initial swing angle setting: Adjust the pendulum to the desired initial swing angle (e.g., 10°, 15°, etc.) using the angle scale.

[0054] After setting the initial angle, the swing arm can be gently fixed to prevent it from deviating from the set angle.

[0055] Step 3: Experimental Operation

[0056] The operator gently releases the pendulum with their hand, allowing the pendulum and pendulum ball to begin swinging freely.

[0057] Observe and record the period, amplitude, relative motion characteristics, or energy conversion process of the pendulum.

[0058] If necessary, adjust the pendulum or pendulum bob parameters to repeat the experiment and compare the results of different settings.

[0059] Step 4: Battery Installation and Power Supply

[0060] Open the cover on the mounting base to expose the battery compartment, insert a standard AA battery into the battery slot, and then close the cover. Beforehand, check that the pendulum drive mechanism is functioning correctly to ensure the experimental equipment operates without errors.

[0061] A pair of pendulums are made to move continuously by a magnetic field generating component, so that students can more easily observe and record the period, amplitude, relative motion characteristics or energy conversion process of the pendulums.

[0062] Step 5: Experiment Completion and Storage

[0063] After demonstrating the double pendulum motion, turn off the power and store the demonstration device properly. The surface of the pendulum rod should be cleaned to prevent corrosion or damage during long-term storage.

[0064] In summary, this utility model of a double pendulum motion demonstrator, employing a double pendulum structure, can intuitively demonstrate complex dynamic characteristics, such as the chaotic phenomena and periodic motion of a double pendulum, providing richer experimental content for physics teaching and research. The adjustable position of the pendulum bob on the pendulum rod enhances experimental diversity, supports research on the influence of changes in the pendulum bob's center of gravity on motion, and further expands the scope of teaching and experimental applications. All parts are easy to disassemble, transport, and store, suitable for use in multiple scenarios, such as classroom teaching or laboratory research, making the demonstrator more flexible and convenient to use. The adjustable pendulum rod length and its graduated scale allow users to quickly and accurately set the pendulum length and initial conditions, improving experimental efficiency. The base of the support frame ensures the stability of the device during experiments, effectively reducing the impact of external interference on experimental results. It can be powered by ordinary AA batteries, is convenient and inexpensive, requires no external power supply, is suitable for various teaching environments, and enhances the demonstrator's practicality and portability. The demonstrator's pendulum rod design is more intuitive and simple to operate, facilitating students' independent completion of experiments, observation, and understanding of the dynamic principles of the double pendulum, deepening their understanding of physical principles, enhancing learning effectiveness, and increasing experimental interest. The flexible adjustment function and stability of each part support repeated experiments, help students intuitively verify mechanical theories, improve their learning interest, and enhance teaching effectiveness.

[0065] Although the present invention has been described in detail above, it is not limited thereto. Those skilled in the art can make modifications based on the principles of the present invention. Therefore, all modifications made in accordance with the principles of the present invention should be understood as falling within the protection scope of the present invention.

Claims

1. A double pendulum motion demonstration device, characterized in that, include: Support frame; A pair of fixed seats installed on the upper part of the support frame; A pair of swing rods, each rotatably connected to a pair of fixed seats at their upper ends; A pair of pendulum drive structures used to drive a pair of pendulum structures to swing relative to a pair of fixed seats; Each pendulum structure includes: a pendulum rod rotatably connected to a corresponding fixed base at its upper part; and multiple pendulum balls of different or identical masses that can be detachably mounted on the pendulum rod. Each pendulum drive structure includes: a magnetic field generating component fixedly installed on the corresponding fixed base; and a magnet fixedly installed on the upper part of the pendulum, which can drive the pendulum to swing relative to the fixed base under the action of the magnetic field generated by the magnetic field generating component.

2. The double pendulum motion demonstrator according to claim 1, characterized in that, The pendulum structure also includes a connecting sleeve mounted on the pendulum, and the pendulum ball can be placed inside the connecting sleeve.

3. The double pendulum motion demonstrator according to claim 2, characterized in that, The magnetic field generating assembly includes a coil mounted on a fixed base and a power supply mounted on the fixed base and electrically connected to the coil.

4. The double pendulum motion demonstrator according to claim 3, characterized in that, The connecting sleeve is a sleeve-shaped connecting sleeve, which is fixedly installed on the clamping clamp, which can clamp onto the swing arm.

5. The double pendulum motion demonstrator according to claim 1, characterized in that, Hooks for easy hanging are installed on the support frame or the fixed base.

6. The double pendulum motion demonstrator according to claim 1 or 5, characterized in that, The bottom of the support frame is a horizontal base for easy placement on a horizontal object.

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