Cross-shaped rotational inertia and rotation law demonstration device

Abstract

The utility model provides a cross-shaped rotational inertia and rotation law demonstration device, and relates to the technical field of teaching experiment instruments. The device comprises a base, a telescopic support, a rotating wheel assembly, a rotating shaft assembly, four rigid body arms, a balancing weight, a heavy hammer and a connecting rope, the bottom of the telescopic support is connected with the base, the top of the telescopic support is rotationally connected with the rotating wheel assembly through the rotating shaft assembly, and the rotating wheel assembly is connected with the rotating shaft assembly through the balancing weight. The ends of the rigid body arms are connected with the rotating wheel assembly, the four rigid body arms are evenly distributed in the circumferential direction of the rotating wheel assembly and are of a cross structure, and each rigid body arm is connected with one balancing weight. The rotating wheel assembly is connected with the heavy hammer through the connecting rope, and the connecting rope can be wound around the rotating wheel assembly.

Description

TECHNICAL FIELD

[0001] The utility model relates to teaching experimental instrument technical field especially is related to a cross type moment of inertia and rotation law demonstration device. BACKGROUND

[0002] In physics teaching, moment of inertia and rotation law are important basic theoretical knowledge. However, the existing related demonstration instruments on the market are either complex in structure, cumbersome to operate and inconvenient for students to quickly understand the experimental principle, or the demonstration effect is not intuitive and the influence of moment of inertia change on the rotation state of rigid body cannot be clearly shown. At the same time, the existing instruments also have deficiencies in stability, precision and other aspects, and it is difficult to meet the needs of high-quality teaching experiments. Therefore, it is of great significance to design a moment of inertia and rotation law demonstration instrument with simple structure, convenient operation, obvious demonstration effect, high stability and good precision for improving teaching quality and helping students better master related knowledge. CONTENT OF THE UTILITY MODEL

[0003] The utility model aims at providing a cross type moment of inertia and rotation law demonstration device, and the preferred technical solutions in the utility model can produce many technical effects, which are described in detail below.

[0004] To achieve the above-mentioned purpose, the utility model provides the following technical solutions:

[0005] The utility model provides a cross type moment of inertia and rotation law demonstration device, which comprises a base, a telescopic support, a rotating wheel assembly, a rotating shaft assembly, rigid arms, counterweights, a weight and a connecting rope, wherein the bottom of the telescopic support is connected with the base, the top of the telescopic support is rotationally connected with the rotating wheel assembly through the rotating shaft assembly, the number of the rigid arms is four, the end of the rigid arm is connected with the rotating wheel assembly, the four rigid arms are evenly distributed along the circumferential direction of the rotating wheel assembly and form a cross structure, one counterweight is connected to each rigid arm, the rotating wheel assembly and the weight are connected through the connecting rope, and the connecting rope can be wound on the rotating wheel assembly.

[0006] Optionally, the upper end surface of the base is provided with a universal level bubble, and the bottom foot is connected with the lower end of the base, and the height adjusting structure is arranged on the bottom foot.

[0007] Optionally, the telescopic support is provided with a telescopic structure.

[0008] Optionally, the rotating shaft assembly comprises a vertical shaft and a horizontal shaft, the end of the horizontal shaft is fixedly connected with the side wall of the vertical shaft, and the horizontal shaft and the vertical shaft are vertically arranged, the vertical shaft is connected with the top of the telescopic support, and the horizontal shaft is rotationally connected with the rotating wheel assembly.

[0009] Optionally, the vertical shaft is provided with a through hole in the vertical direction, the vertical shaft is provided with a threaded hole in the horizontal direction, the top of the telescopic support is inserted into the through hole, a bolt is connected in the threaded hole, and the end of the bolt can abut against the side wall of the telescopic support.

[0010] Optionally, the inner ring of the runner assembly is inlaid with a bearing, and the inner ring of the bearing is connected with the horizontal shaft.

[0011] Optionally, the runner assembly comprises a connecting sleeve and a roller, the rotating shaft assembly is inserted into the connecting sleeve, the rotating shaft assembly is connected with the connecting sleeve through a bearing, and the end of the connecting sleeve is connected with the end of the roller through a screw;

[0012] The circumferential side wall of the connecting sleeve is provided with connecting holes, the number of the connecting holes is four, and the connecting holes are distributed in the circumferential direction of the runner assembly, and the connecting holes are threadedly connected with the end of the rigid arm.

[0013] The circumferential side wall of the roller is provided with an annular wire groove, one end of the connecting rope is connected with the annular wire groove, and the connecting rope can be wound on the annular wire groove.

[0014] Optionally, an adjusting piece is arranged between the rigid arm and the counterweight, the outer wall of the rigid arm is provided with an annular clamping groove, the number of the annular clamping grooves is at least two, the counterweight is provided with a moving channel and an adjusting hole, the rigid arm passes through the moving channel, the adjusting piece is connected with the adjusting hole, and the end of the adjusting piece can be inserted into the annular clamping groove.

[0015] Optionally, the adjusting piece comprises a ball, a spring and a screw, the spring is located between the ball and the screw, the ball is close to the rigid arm, and the screw is threadedly connected with the adjusting hole.

[0016] The cross-shaped rotating inertia and rotating law demonstration device is simple in overall structural design, and students can operate it without complex operation training, and the whole experiment process can be completed through simple operations such as adjusting the height of the telescopic support, moving the position of the counterweight and releasing the weight. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description only show some of the embodiments of the present application, and for those skilled in the art, other drawings can also be obtained from these drawings without any creative effort.

[0018] Figure 1 is a structural schematic view of a cross-shaped rotational inertia and rotational law demonstration device provided by the embodiments of the present application;

[0019] Figure 2 is a partial part section view of a cross-shaped rotational inertia and rotational law demonstration device provided by the embodiments of the present application;

[0020] Figure 3 is a section view of a rotating shaft assembly of a cross-shaped rotational inertia and rotational law demonstration device provided by the embodiments of the present application;

[0021] Figure 4 is a structural schematic view of a rigid body arm and counterweight block connection of a cross-shaped rotational inertia and rotational law demonstration device provided by the embodiments of the present application;

[0022] Figure 5 is a structural schematic view of a counterweight block of a cross-shaped rotational inertia and rotational law demonstration device provided by the embodiments of the present application.

[0023] In the figure, 1, base; 11, universal level bubble; 12, foot;

[0024] 2, telescopic support;

[0025] 3, rotating wheel assembly; 31, connecting sleeve; 311, connecting hole; 32, roller; 321, annular wire slot;

[0026] 4, rotating shaft assembly; 41, vertical shaft; 411, through hole; 412, threaded hole; 42, horizontal shaft;

[0027] 5, rigid body arm; 51, annular clamping slot;

[0028] 6, counterweight block; 61, moving channel; 62, adjusting hole;

[0029] 7, weight;

[0030] 8, connecting rope;

[0031] 9, adjusting piece; 91, ball; 92, spring; 93, screw. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical scheme and advantages of the utility model more clear, the technical scheme of the utility model will be described in detail below. Obviously, the described embodiments are only part of the embodiments of the utility model, not all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by the ordinary skilled in the art without creative labor belong to the scope of the utility model.

[0033] In the description of the utility model, it needs to be explained that, unless otherwise specified, the meaning of "multiple" is two or more than two;The orientation or position relationship indicated by the terms "upper", "lower", "left", "right", "inner", "outer", "front end", "rear end", "head", "tail" and the like is based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the utility model and simplifying the description, and is not indicative or suggestive of the device or element indicated must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the utility model. In addition, the terms "first", "second", "third" and the like are only for the purpose of description, and cannot be understood as indicative or suggestive of relative importance.

[0034] In the description of the utility model, it also needs to be explained that, unless otherwise specified and limited, the terms "mounting", "connecting", "connecting" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected;It can be mechanically connected, or it can be electrically connected;It can be directly connected, or it can be indirectly connected through an intermediate medium. For the ordinary skilled in the art, the specific meaning of the above terms in the utility model can be understood according to the specific circumstances.

[0035] The utility model provides a kind of cross type rotational inertia and rotation law demonstration device, including base 1, telescopic support 2, rotating wheel component 3, rotating shaft component 4, rigid arm 5, counterweight 6, weight 7 and connecting rope 8, wherein, the bottom of telescopic support 2 is connected with base 1, the top of telescopic support 2 is rotationally connected with rotating wheel component 3 by rotating shaft component 4, the number of rigid arm 5 is four, the end of rigid arm 5 is connected with rotating wheel component 3, four rigid arm 5 is evenly distributed and presents cross structure along the circumferential direction of rotating wheel component 3, four rigid arm 5 is centrally symmetric with rotating shaft component 4 as center, each rigid arm 5 is connected with a counterweight 6, rotating wheel component 3 is connected with weight 7 by connecting rope 8 and connecting rope 8 can be wound on rotating wheel component 3.The utility model provides a kind of cross type rotational inertia and rotation law demonstration device, overall structure design is simple, student can operate without complex operation training, by simply adjusting telescopic support 2 height, moving counterweight 6 position and releasing weight 7 etc.

[0036] As optional implementation, the upper end surface of the base 1 is provided with a universal level bubble 11, which can be a high-precision disc scale universal level bubble. The lower end of the base 1 is connected with a foot 12, which is provided with a height adjusting structure. The number of the foot 12 can be three or more. The base 1 is made of 45# steel, which has high strength and stability, and can provide a stable support foundation for the entire demonstration device, ensuring that the demonstration device will not easily shake or displace during the experiment. The universal level bubble 11 and the foot 12 can conveniently, quickly, and accurately adjust the level of the demonstration device, making the demonstration device have good stability and further ensuring the accuracy of the experiment. Before the experiment, by observing the universal level bubble 11, the foot 12 is used to adjust the angles of the base 1, so that the demonstration device is in a horizontal state, further ensuring the accuracy of the experiment.

[0037] As optional implementation, the telescopic support 2 is provided with a telescopic structure, which can conveniently adjust the height of the demonstration device.

[0038] As optional implementation, the rotating shaft component 4 includes a vertical shaft 41 and a horizontal shaft 42. The end of the horizontal shaft 42 is fixedly connected with the side wall of the vertical shaft 41, and the horizontal shaft 42 and the vertical shaft 41 are vertically arranged. The vertical shaft 41 is connected with the top of the telescopic support 2, and the horizontal shaft 42 is rotationally connected with the rotating wheel component 3.

[0039] As an optional implementation, the vertical shaft 41 is provided with a through hole 411 in the vertical direction, and the vertical shaft 41 is provided with a threaded hole 412 in the horizontal direction, the top of the telescopic support 2 extends into the through hole 411, and a bolt is connected in the threaded hole 412 and the end of the bolt can abut against the side wall of the telescopic support 2.

[0040] As an optional implementation, the inner ring of the runner assembly 3 is inlaid with a bearing, and the inner ring of the bearing is connected with the horizontal shaft 42. The bearing is made of bearing steel material, has the characteristics of high limit speed and low friction coefficient (0.0010-0.0015), and can ensure the smoothness and stability of the rotation of the runner assembly 3.

[0041] As an optional implementation, the runner assembly 3 includes a connecting sleeve 31 and a roller 32, the rotating shaft assembly 4 extends into the connecting sleeve 31, and the rotating shaft assembly 4 is connected with the connecting sleeve 31 through a bearing, and the end of the connecting sleeve 31 is connected with the end of the roller 32 through a screw;

[0042] The circumferential side wall of the connecting sleeve 31 is provided with a connecting hole 311, the number of the connecting hole 311 is four and they are all distributed in the circumferential direction of the runner assembly 3, and the connecting hole 311 is threadedly connected with the end of the rigid arm 5;

[0043] The circumferential side wall of the roller 32 is provided with an annular wire groove 321, the annular wire groove 321 is connected with one end of the connecting rope 8 and the connecting rope 8 can be wound on the annular wire groove 321. When the connecting rope 8 is completely wound on the annular wire groove 321, the weight 7 is loosened, and in the falling process of the weight 7, the runner assembly 3 and the rigid arm 5 are driven to rotate. The weight 7 is equivalent to exerting a constant external torque on the runner assembly 3 and the rigid arm 5. The arrangement of the weight 7 and the roller 32 ensures the stability of the exertion of the external torque, thereby ensuring the reliability and repeatability of the experimental results.

[0044] As an optional implementation, the rigid arm 5 is made of metal material, the counterweight 6 is made of copper material, and the adjusting piece 9 is arranged between the rigid arm 5 and the counterweight 6, and the adjusting piece 9 is used to adjust the position of the counterweight 6 on the rigid arm 5. By changing the position of the counterweight 6 on the rigid arm 5, that is, changing the distance between the counterweight 6 and the rotating shaft assembly 4, the adjustment of the rigid moment of inertia is realized. The adjusting piece 9 increases the safety and controllability of the experiment. The outer wall of the rigid arm 5 is provided with an annular clamping groove 51, the number of the annular clamping groove 51 is at least two, the counterweight 6 is provided with a moving channel 61 and an adjusting hole 62, the rigid arm 5 passes through the moving channel 61, the adjusting piece 9 is connected with the adjusting hole 62, and the end of the adjusting piece 9 can extend into the annular clamping groove 51. The positions of the annular clamping grooves 51 on each rigid arm 5 are consistent, so as to ensure that the distances between the counterweights 6 on each rigid arm 5 and the rotating shaft assembly 4 are consistent.

[0045] As an optional implementation, the adjusting member 9 comprises a ball 91, a spring 92 and a screw 93, the spring 92 is located between the ball 91 and the screw 93, the ball 91 is close to the rigid arm 5, and the screw 93 is in threaded connection with the adjusting hole 62. When it is required to change the position of the weight block 6 on the rigid arm 5, the screw 93 is first screwed outwards, the spring 92 is elongated, the elastic force of the spring 92 on the ball 91 is reduced, the ball 91 is separated from the annular clamping groove 51 at this position when the weight block 6 is moved along the length direction of the rigid arm 5, the ball 91 is arranged in the annular clamping groove 51 at the position when the weight block 6 is moved to the specified position, and the screw 93 is reversely screwed, so that the spring 92 is compressed, the elastic force of the spring 92 on the ball 91 is increased, and the ball 91 is clamped in the annular clamping groove 51 and is not easy to be separated. The annular clamping groove 51 is matched with the ball 91, so that the stability of the movement of the weight block 6 and the positioning accuracy are ensured.

[0046] The experimental operation of the cross-shaped rotational inertia and rotational law demonstration device,

[0047] (I) Experimental preparation

[0048] Place the demonstration device on a horizontal table top, observe the universal level bubble 11, adjust the three feet 12 to make the demonstration device in a horizontal state, and then fix the telescopic support 2;

[0049] Move all the weight blocks 6 on the rigid arms 5 to the positions closest to the rotating shaft assembly 4;

[0050] Wind the connecting rope 8 with the weight 7 on the annular wire groove 321 on the roller 32, slowly lift the weight 7, and make the weight 7 rise to the top.

[0051] (II) Experimental operation

[0052] Release the weight 7, at this time, the rigid arm 5 starts to rotate, and it can be observed that the rotating speed gradually increases. This is because when the weight block 6 is located at the position closest to the rotating shaft assembly 4, the rotational inertia of the rigid body is small, and according to the rotational law of the rigid body, under the action of the same external torque, the angular acceleration is large, and thus the angular velocity is also large.

[0053] After the rigid arm 5 stops rotating, move the four copper weight blocks 6 to the positions farthest from the rotating shaft assembly 4.

[0054] Wind the connecting rope 8 with the weight 7 on the annular wire groove 321 on the roller 32 again, so that the weight 7 rises to the top.

[0055] The release weight 7 can be seen that the rigid arm 5 rotation speed is significantly slower than the first operation. This is due to the weight 6 to move away from the shaft assembly 4 position, the rigid moment of inertia is large, under the same external torque, the angular acceleration is small, the angular velocity is small.

[0056] (Three) matters needing attention

[0057] The four weight blocks 6 should be kept in the center of the symmetrical position to ensure the smooth rotation, to avoid uneven force affecting the experimental results.

[0058] When sliding weight block 6, the action should be light, when feeling the ball 91 card into the ring card slot 51, can not be too large force to pull out the ring card slot 51, to prevent damage to the weight block 6 or the structure of the ring card slot 51, affect the normal experiment.

[0059] Regularly check and maintain the bearing and other rotating parts, to ensure its good rotation performance, if found abnormal wear and tear, in time for replacement.

[0060] The above, only for the specific embodiments of the present application, but the scope of protection of the present application is not limited to this, any skilled in the art of the technical personnel in the present application disclosed in the technical range, can easily think of changes or replacement, should be covered in the scope of protection of the present application. Therefore, the scope of protection of the present application should be subject to the scope of protection of the claims.

Claims

1. A device for demonstrating the moment of inertia and the law of rotation of a cross, characterized in that, The utility model relates to a kind of rotating arm, including base (1), telescopic support (2), rotating wheel assembly (3), rotating shaft assembly (4), rigid arm (5), counterweight (6), weight (7) and connecting rope (8), wherein, The bottom of the telescopic support (2) is connected with the base (1), the top of the telescopic support (2) is rotatably connected with the rotating wheel assembly (3) through the rotating shaft assembly (4), the number of the rigid arm (5) is four, the end of the rigid arm (5) is connected with the rotating wheel assembly (3), four rigid arms (5) are evenly distributed along the circumferential direction of the rotating wheel assembly (3) and form a cross structure, one counterweight (6) is connected to each rigid arm (5), the rotating wheel assembly (3) is connected with the weight (7) through the connecting rope (8), and the connecting rope (8) can be wound on the rotating wheel assembly (3).

2. The cross-shaped rotational inertia and rotational law demonstration device according to claim 1, characterized in that, The upper end surface of the base (1) is provided with a universal level bubble (11), and the lower end of the base (1) is connected with a foot (12), and the foot (12) is provided with a height adjusting structure.

3. The device according to claim 1, wherein The telescopic support (2) is provided with a telescopic structure.

4. The cross-shaped moment of inertia and rotational law demonstration device according to claim 1, characterized in that, The rotating shaft assembly (4) includes a vertical shaft (41) and a horizontal shaft (42), the end of the horizontal shaft (42) is fixedly connected with the side wall of the vertical shaft (41), and the horizontal shaft (42) and the vertical shaft (41) are vertically arranged, the vertical shaft (41) is connected with the top of the telescopic support (2), and the horizontal shaft (42) is rotatably connected with the rotating wheel assembly (3).

5. The device according to claim 4, wherein The vertical shaft (41) is provided with a through hole (411) in the vertical direction, the vertical shaft (41) is provided with a threaded hole (412) in the horizontal direction, the top of the telescopic support (2) extends into the through hole (411), a bolt is connected in the threaded hole (412), and the end of the bolt can abut against the side wall of the telescopic support (2).

6. The cross-shaped moment of inertia and rotational law demonstration device according to claim 4, characterized in that, The inner ring of the bearing is embedded in the inner ring of the rotating wheel assembly (3).

7. The cross-shaped rotational inertia and rotational law demonstration device according to claim 1, characterized in that, The rotating wheel assembly (3) includes a connecting sleeve (31) and a roller (32), the rotating shaft assembly (4) extends into the connecting sleeve (31), and the rotating shaft assembly (4) is connected with the connecting sleeve (31) through a bearing, the end of the connecting sleeve (31) is connected with the end of the roller (32) through a screw; The circumferential side wall of the connecting sleeve (31) is provided with a connecting hole (311), the number of the connecting hole (311) is four, and they are distributed in the circumferential direction of the rotating wheel assembly (3), and the connecting hole (311) is threadedly connected with the end of the rigid arm (5); The circumferential side wall of the roller (32) is provided with an annular wire groove (321), one end of the connecting rope (8) is connected with the annular wire groove (321), and the connecting rope (8) can be wound on the annular wire groove (321).

8. The device of claim 1, wherein, The adjusting member (9) is arranged between the rigid arm (5) and the counterweight (6), the outer wall of the rigid arm (5) is provided with annular clamping grooves (51), the number of the annular clamping grooves (51) is at least two, the counterweight (6) is provided with a moving channel (61) and an adjusting hole (62), the rigid arm (5) passes through the moving channel (61), the adjusting member (9) is connected with the adjusting hole (62), and the end of the adjusting member (9) can extend into the annular clamping groove (51).

9. The device according to claim 8, wherein, The adjusting member (9) comprises a ball (91), a spring (92) and a screw (93), the spring (92) is located between the ball (91) and the screw (93), the ball (91) is close to the rigid arm (5), and the screw (93) is in threaded connection with the adjusting hole (62).

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