CN212276648U - A mechanical teaching aid component that can display axial force, bending moment or torque - Google Patents
A mechanical teaching aid component that can display axial force, bending moment or torque Download PDFInfo
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- CN212276648U CN212276648U CN201922179527.6U CN201922179527U CN212276648U CN 212276648 U CN212276648 U CN 212276648U CN 201922179527 U CN201922179527 U CN 201922179527U CN 212276648 U CN212276648 U CN 212276648U
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Abstract
本实用新型公开了一种可显示轴力、弯矩或扭矩的力学教具构件，由外壳结构、激光发射系统、光传导系统组成。所述的外壳结构由弹性壳体、轴力指示窗、弯矩指示窗、扭矩指示窗、承载片组成；所述的激光发射系统由轴力激光发射器、弯矩激光发射器、扭矩激光发射器组成；所述的光传导系统由轴力反光镜、弯矩反光镜、扭矩反光镜组成。构件受轴力时长度发生变化，激光经轴力反光镜反射后光点在轴力指示窗上指示出轴力数值和方向；构件受弯矩时，两底面夹角发生变化，激光经弯矩反光镜反射后光点在弯矩指示窗上指示出弯矩数值和方向；构件受扭矩时，两底面发生相对转动，激光经扭矩反光镜反射后光点在扭矩指示窗上指示出扭矩数值和方向。
The utility model discloses a mechanics teaching aid component capable of displaying axial force, bending moment or torque, which is composed of a shell structure, a laser emission system and a light conduction system. The shell structure is composed of an elastic shell, an axial force indicator window, a bending moment indicator window, a torque indicator window, and a carrier sheet; the laser emission system is composed of an axial force laser transmitter, a bending moment laser transmitter, and a torque laser transmitter. The light transmission system is composed of an axial force reflector, a bending moment reflector and a torque reflector. When the component is subjected to axial force, the length changes, and after the laser is reflected by the axial force mirror, the light spot indicates the value and direction of the axial force on the axial force indicator window; After reflection by the mirror, the light spot indicates the value and direction of the bending moment on the bending moment indicator window; when the component is subjected to torque, the two bottom surfaces rotate relative to each other, and after the laser is reflected by the torque mirror, the light spot indicates the torque value and direction on the torque indicator window. direction.
Description
Technical Field
The utility model relates to a teaching aid field specifically is a can show mechanics teaching aid component of axial force, moment of flexure or moment of torsion.
Background
The places using mechanics knowledge in life are everywhere, and usually, the object is not necessarily subjected to a single force, but the stress state of the object is difficult to perceive intuitively. Most colleges and universities set up courses of structural mechanics, material mechanics, theoretical mechanics and the like, the courses are professional basic courses of most of science and engineering subjects, but the mechanics courses are abstract and difficult to understand for students, and abstract mechanics knowledge can become visual and vivid by means of the teaching aids, so that the students can deepen understanding of the mechanics knowledge.
The Chinese patent of invention CN201810316796.X discloses a structural mechanics teaching aid, which comprises a stress component, an elastic connecting ring and a support, wherein the deformation state of the stress component after load is applied is observed. However, the invention cannot visually display the axial force applied to the structure and give specific values. The invention patent CN201510783859.9 discloses a portable assembled theoretical mechanics teaching aid, the whole device is arranged in a portable box, and teachers can assemble teaching aid common parts according to an assembly method schematic diagram. The invention has complex structure, high cost, is not suitable for large-scale popularization, and can not visually display the specific numerical value of the axial force, the torque or the bending moment applied to the structure.
Generally, the mechanical teaching aid that teaching was used is less at present, does not have a teaching aid that not only economy but also can directly perceivedly show axial force, moment of flexure or moment of torsion moreover, is difficult to carry out extensive life science popularization and effectual mechanics course teaching.
Disclosure of Invention
To the problem, the utility model provides a can show mechanical teaching aid component of axial force, moment of flexure or moment of torsion can satisfy the needs of life science popularization and mechanical course teaching, lets the state of people's perception object directly perceived atress, helps the student to the understanding of mechanics knowledge.
In order to achieve the above purpose, the utility model adopts the following technical scheme:
the utility model provides a can show mechanics teaching aid component of axial force, moment of flexure and moment of torsion which characterized in that: the laser light guide device consists of a shell structure, a laser emission system and a light conduction system. The shell structure comprises an elastic shell, an axial force indicating window, a bending moment indicating window, a torque indicating window and a bearing sheet. The laser emission system consists of an axial force laser emitter, a bending moment laser emitter and a torque laser emitter, each laser emitter is provided with a built-in micro battery as a power supply, and the on-off state of each laser emitter can be controlled according to requirements. The light conduction system consists of two axial force reflectors, two bending moment reflectors and a torque reflector.
Furthermore, the shell structure is not transparent except for the indication window part, and the indication window part is semi-transparent so as to observe the position of the light spot and prevent the harm to an observer caused by the over-strong laser.
Furthermore, the elastic size of the elastic shell meets the requirement that the light spot can effectively move after the component is subjected to micro deformation; the axial force indicating window and the bending moment indicating window are respectively positioned on the opposite sides of the outer surface of the cylinder wall of the shell structure and are axially distributed in parallel; the torque indicating window is positioned between the axial force indicating window and the bending moment indicating window and is distributed annularly. The bearing sheets are distributed at two ends of the elastic shell.
Furthermore, the axial force indication window, the bending moment indication window and the torque indication window are respectively marked with scales for indicating the size and direction marks of the axial force, the bending moment and the torque.
Further, the bearing sheet has a rough surface to increase friction and facilitate the application of load to the member.
Furthermore, the axial force laser emitter and the bending moment laser emitter are respectively positioned at two ends of the same diameter of the inner wall of the bottom surface, and the laser emitting directions respectively form acute angles with the same degree with the diameter, so that the axial force laser and the bending moment laser are reflected and then respectively shot at the 0-scale position of the corresponding indicating window.
Furthermore, the torque laser emitter is positioned at the circle center of the inner wall of the bottom surface, and the laser emitting direction is vertical to the bottom surface.
Furthermore, the axial force reflector is a slender rectangle, one is positioned at the position, close to the bending moment laser emitter, of the circle center of the inner wall of the bottom surface of the laser emitting end, and the other is positioned at the position, close to the circle center of the inner wall of the bottom surface of the other end, of the circle center, so that light spots are projected on the scale 0 of the axial force indicating window after the laser is reflected twice.
Furthermore, the bending moment reflector is a slender rectangle, one is positioned at the position, close to the axial force laser emitter, of the upper circle center of the inner wall of the bottom surface of the laser emitting end, and the other is positioned at the position, close to the lower circle center of the inner wall of the bottom surface of the other end, so that light spots are projected on the scale 0 of the bending moment indicating window after the laser is reflected twice.
Furthermore, the torque reflector is circular and is positioned at the center of the bottom inner wall of the end opposite to the laser emergent end, and a certain included angle is formed between the mirror surface and the light emergent direction so as to meet the requirement that laser is reflected and then is irradiated on the scale 0 of the torque indicating window.
The principle of axial force display is as follows: when the member is under tension, the length of the member is increased, and the geometric path of the laser emitted by the axial force laser emitter is increased, so that a light spot moves to a laser emergent end on the wall of the shell structure; when the component is stressed, the length of the component is reduced, and the geometric path of the laser emitted by the axial force laser emitter is reduced, so that the light spot moves to the other end on the wall of the shell structure; after the shaft force is removed, the member returns to the initial state, and the light spot returns to the 0 scale.
The display principle of the bending moment is as follows: when the component is subjected to negative bending moment, the included angle formed by the two bottom surfaces changes, and the included angle between incident light and reflected light is increased when laser emitted by the bending moment laser emitter is reflected, so that a light spot moves to a laser emitting end on the wall of the shell structure; when the component is subjected to positive bending moment, the included angle between incident light and reflected light becomes smaller when the laser emitted by the bending moment laser emitter is reflected, so that the light spot moves to the other end on the wall of the shell structure; after the bending moment is removed, the member returns to the initial state, and the light spot returns to the 0 scale.
The torque display principle is as follows: when the component is subjected to positive torque, the torque reflector rotates anticlockwise relative to the laser emitting end, so that the light spot moves along a certain direction on the wall of the shell structure; when the component is subjected to negative torque, the torque reflector rotates clockwise relative to the laser emitting end, so that the light spot moves along the other direction on the wall of the shell structure; after the torque is removed, the member returns to the initial state and the spot returns to the 0 scale.
The utility model relates to a can show mechanics teaching aid component of axial force, moment of flexure or moment of torsion, application method specifically includes following step:
(1) calibrating an axial force indication scale value through a standard axial force sensor, calibrating a bending moment indication scale value through a standard bending moment sensor, and calibrating a torque indication scale value through a standard torque sensor;
(2) the angle and the position of the component are adjusted, so that the indication window is convenient to observe;
(3) opening a required laser transmitter switch according to the requirement, and applying an external load to the component;
(4) and observing an indication window of the component, and reading the direction and the magnitude of the axial force, the bending moment or the torque applied to the component.
The utility model relates to a can show mechanics teaching aid component of axial force, moment of flexure or moment of torsion, its characteristics are:
(1) the magnitude and direction of axial force, bending moment or torque are visually displayed;
(2) the single-purpose combined type solar water heater can be used singly, and can also be assembled into various structural forms according to the requirements;
(3) the change of small axial force, bending moment or torque is intuitively reflected;
(4) the power is supplied by a built-in micro battery without an external power supply.
Drawings
In order to illustrate the present invention or prior art more clearly, the drawings that are needed to be used in the description of the present invention or prior art will be described.
FIG. 1 is a cross-sectional view of the present invention;
FIG. 2 is a cross-sectional view taken along line a-a of the present invention;
FIG. 3 is a cross-sectional view taken along line b-b of the present invention;
fig. 4 is a c-c sectional view of the present invention;
FIG. 5 is a schematic drawing of the tension of the present invention;
fig. 6 is a schematic view of the bending moment of the present invention;
fig. 7 is a schematic diagram of the torque applied by the present invention;
illustration of the drawings: 11-axial force laser transmitter; 12-torque laser transmitter; 13-bending moment laser emitter; 21-axial force reflector, 22-bending moment reflector; 23-torque mirror; 31-bending moment indicator window; 32-axial force indicator window; 33-torque indicator window; 4-an elastic shell; 5-a carrier sheet; 6-laser light.
Detailed Description
The utility model provides an assembled mechanics teaching aid component that can show axial force, for making the utility model discloses a purpose, technical scheme are clearer, more clear and definite, and it is right below to combine the drawing the utility model discloses a detailed description is carried out to the embodiment.
As shown in figure 1, a can show mechanics teaching aid component of axial force, moment of flexure and moment of torsion, its characterized in that: the laser light guide device consists of a shell structure, a laser emission system and a light conduction system. The shell structure comprises an elastic shell 4, an axial force indicating window 31, a bending moment indicating window 32, a torque indicating window 33 and a bearing sheet 5. The laser emission system consists of an axial force laser emitter 11, a bending moment laser emitter 12 and a torque laser emitter 13, wherein each laser emitter is provided with a built-in micro battery as a power supply, and the on-off state of each laser emitter can be controlled according to requirements. The light conduction system consists of two axial force reflectors 21, two bending moment reflectors 22 and a torque reflector 23.
Furthermore, the shell structure is opaque except for the indicating window part, and the indicating window part is semi-transparent, so that the position of a light spot can be observed and the harm to an observer caused by over-strong laser can be prevented.
Furthermore, the elastic size of the elastic shell 4 meets the requirement that the light spot can effectively move after the component is subjected to micro deformation; the axial force indicating window 31 and the bending moment indicating window 32 are respectively positioned on the opposite sides of the outer surface of the cylinder wall of the shell structure and are axially distributed in parallel; the torque indicating window 33 is located between the axial force indicating window 31 and the bending moment indicating window 32 and is distributed annularly. The bearing sheets 5 are distributed at two ends of the elastic shell 4.
Further, the axial force indication window 31, the bending moment indication window 32 and the torque indication window 33 are respectively marked with scales for indicating the size and direction marks of the axial force, the bending moment and the torque.
Further, the bearing sheet 5 has a rough surface to increase friction and facilitate the application of load to the member.
Further, the axial force laser emitter 11 and the bending moment laser emitter 12 are respectively located at two ends of the same diameter of the inner wall of the bottom surface, and the laser emitting directions respectively form acute angles with the same degree as the diameter, so that the axial force laser and the bending moment laser are reflected and then respectively hit at the 0-scale position of the corresponding indicating window.
Further, the torque laser emitter 13 is located at the center of the inner wall of the bottom surface, and the laser emitting direction is perpendicular to the bottom surface.
Further, the axial force reflecting mirror 21 is a slender rectangle, one is located at a position, close to the bending moment laser emitter 12, of the lower circle center of the inner wall of the bottom surface of the laser emitting end, and the other is located at a position, close to the upper circle center of the inner wall of the bottom surface of the other end, so that a light spot is projected on the 0 scale of the axial force indicating window 31 after the laser is reflected twice.
Further, the bending moment reflector 22 is a slender rectangle, one is located at a position where the circle center of the inner wall of the bottom surface of the laser emitting end is offset upward and close to the axial force laser emitter 11, and the other is located at a position where the circle center of the inner wall of the bottom surface of the other end is offset downward, so that the light spot is projected on the 0 scale of the bending moment indication window 32 after the laser is reflected twice.
Furthermore, the torque reflector 23 is circular and located at the center of the bottom inner wall of the end opposite to the laser emitting end, and the mirror surface and the light emitting direction form a certain included angle to meet the requirement that the laser is reflected and then is projected on the 0 scale of the torque indicating window 33.
The principle of axial force display is as follows: when the member is under tension, the length of the member is increased, and the geometric path which is passed by laser emitted by the axial force laser emitter 11 is increased, so that a light spot moves to a laser emergent end on the wall of the shell structure; the length of the component is reduced when the component is pressed, the geometric path of the laser emitted by the axial force laser emitter 11 is reduced, and the light spot moves to the other end on the wall of the shell structure; after the shaft force is removed, the member returns to the initial state, and the light spot returns to the 0 scale.
The display principle of the bending moment is as follows: when the component is subjected to negative bending moment, the included angle formed by the two bottom surfaces changes, and the included angle between incident light and reflected light is increased when laser emitted by the bending moment laser emitter 12 is reflected, so that a light spot moves to a laser emitting end on the wall of the shell structure; when the component is subjected to positive bending moment, the included angle between incident light and reflected light becomes smaller when the laser emitted by the bending moment laser emitter 12 is reflected, so that a light spot moves to the other end on the wall of the shell structure; after the bending moment is removed, the member returns to the initial state, and the light spot returns to the 0 scale.
The torque display principle is as follows: when the component is subjected to positive torque, the torque reflector 23 rotates anticlockwise relative to the laser emitting end, so that the light spot moves along a certain direction on the wall of the shell structure; when the component is subjected to negative torque, the torque reflector 23 rotates clockwise relative to the laser emitting end, so that the light spot moves along the other direction on the wall of the shell structure; after the torque is removed, the member returns to the initial state and the spot returns to the 0 scale.
The utility model relates to a can show mechanics teaching aid component of axial force, moment of flexure or moment of torsion, application method specifically includes following step:
(1) calibrating an axial force indication scale value through a standard axial force sensor, calibrating a bending moment indication scale value through a standard bending moment sensor, and calibrating a torque indication scale value through a standard torque sensor;
(2) the angle and the position of the component are adjusted, so that the indication window is convenient to observe;
(3) opening a required laser transmitter switch according to the requirement, and applying an external load to the component;
(4) and observing an indication window of the component, and reading the direction and the magnitude of the axial force, the bending moment or the torque applied to the component.
The utility model relates to a can show mechanics teaching aid component of axial force, moment of flexure or moment of torsion, its characteristics are:
(1) the magnitude and direction of axial force, bending moment or torque are visually displayed;
(2) the single-purpose combined type solar water heater can be used singly, and can also be assembled into various structural forms according to the requirements;
(3) the change of small axial force, bending moment or torque is intuitively reflected;
(4) the power is supplied by a built-in micro battery without an external power supply.
Claims (5)
1. The utility model provides a can show mechanics teaching aid component of axial force, moment of flexure or moment of torsion which characterized in that: the device consists of a shell structure, a laser emission system and a light conduction system; the shell structure consists of an elastic shell, an axial force indicating window, a bending moment indicating window, a torque indicating window and a bearing sheet; the laser emission system consists of an axial force laser emitter, a bending moment laser emitter and a torque laser emitter; the light conduction system consists of two axial force reflectors, two bending moment reflectors and a torque reflector.
2. A mechanics teaching aid component displaying axial force, bending moment or torque as claimed in claim 1 wherein: the shell structure is not transparent except the indicating window, and the indicating window is semi-transparent so as to clearly observe light spots and prevent laser from causing damage; the axial force indicating window and the bending moment indicating window are respectively positioned on the opposite sides of the outer surface of the cylinder wall of the shell structure and are axially distributed in parallel; the torque indicating window is located between the axial force indicating window and the bending moment indicating window and distributed annularly.
3. A mechanics teaching aid component displaying axial force, bending moment or torque as claimed in claim 1 wherein: the axial force laser emitter and the bending moment laser emitter are respectively positioned at two ends of the same diameter of the inner wall of the bottom surface, and the emergent directions of the lasers form acute angles with the same degree with the diameter respectively so as to meet the requirement that the axial force laser and the bending moment laser are reflected and then respectively hit at the 0 scale of the corresponding indicating window; the torque laser transmitter is positioned at the circle center of the inner wall of the bottom surface, and the laser emitting direction is vertical to the bottom surface; the axial force reflector is a slender rectangle, one axial force reflector is positioned at the position, close to the bending moment laser emitter, of the lower circle center of the inner wall of the bottom surface of the laser emergent end, and the other axial force reflector is positioned at the position, close to the bending moment laser emitter, of the upper circle center of the inner wall of the bottom surface of the other end, so that light spots are projected to the scale 0 of the axial force indicating window after the laser is; the bending moment reflector is a slender rectangle, one side of the bending moment reflector is positioned at the position, close to the axial force laser emitter, of the upper circle center of the inner wall of the bottom surface at the laser emergent end, and the other side of the bending moment reflector is positioned at the position, close to the lower circle center, of the inner wall of the bottom surface at the other end, so that light spots can be projected to the scale 0 of the bending moment indicating window after the; the torque reflector is circular and is positioned at the circle center of the inner wall of the bottom surface of the end opposite to the laser emergent end, and the mirror surface and the light emergent direction form a certain included angle so as to meet the requirement that laser is reflected and then is shot at the 0-scale position of the torque indicating window.
4. A mechanics teaching aid component displaying axial force, bending moment or torque as claimed in claim 1 wherein: the axial force indicating window, the bending moment indicating window and the torque indicating window are respectively marked with scales for indicating the size and direction marks of the axial force, the bending moment and the torque; the elastic size of the elastic shell meets the requirement that the light spot can effectively move after the component is subjected to micro deformation; when the length of the component is subjected to axial force changes, the geometric path of laser emitted by an axial force laser emitter changes correspondingly, so that the position of a light spot changes, a corresponding numerical value can be read on an axial force indicating window and the direction is confirmed, the component returns to the initial state after the axial force is removed, and the light spot returns to 0 scale; when the member is subjected to bending moment, an included angle formed by two bottom surfaces is changed, the angle formed by incident light and reflected light when the laser emitted by the bending moment laser emitter is reflected is correspondingly changed, so that the position of a light spot is changed, a corresponding numerical value can be read on the bending moment indicating window and the direction is confirmed, the member returns to the initial state after the bending moment is removed, and the light spot returns to the scale of 0; when the component receives torque, the torque reflector rotates relative to the laser emitting end to cause the position of the light spot to change, corresponding numerical values can be read on the torque indicating window and the direction can be confirmed, the component restores to the initial state after the torque is removed, and the light spot returns to the scale of 0.
5. A mechanics teaching aid component displaying axial force, bending moment or torque as claimed in claim 1 wherein: the axial force laser transmitter, the bending moment laser transmitter and the torque laser transmitter are provided with built-in micro batteries as power supplies, and the on-off state of each laser transmitter can be controlled according to requirements.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201922179527.6U CN212276648U (en) | 2019-12-09 | 2019-12-09 | A mechanical teaching aid component that can display axial force, bending moment or torque |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201922179527.6U CN212276648U (en) | 2019-12-09 | 2019-12-09 | A mechanical teaching aid component that can display axial force, bending moment or torque |
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| CN212276648U true CN212276648U (en) | 2021-01-01 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110796929A (en) * | 2019-12-09 | 2020-02-14 | 山东科技大学 | Mechanics teaching aid component capable of displaying axial force, bending moment or torque |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110796929A (en) * | 2019-12-09 | 2020-02-14 | 山东科技大学 | Mechanics teaching aid component capable of displaying axial force, bending moment or torque |
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Granted publication date: 20210101 Termination date: 20211209 |