CN219066304U

CN219066304U - Bending deformation experiment teaching aid for beam

Info

Publication number: CN219066304U
Application number: CN202223273841.9U
Authority: CN
Inventors: 侯少宇; 杨澜; 刘逸亨; 廖健智; 卢信昌; 徐大用
Original assignee: Shenzhen Technology University
Current assignee: Shenzhen Technology University
Priority date: 2022-12-07
Filing date: 2022-12-07
Publication date: 2023-05-23
Anticipated expiration: 2032-12-07

Abstract

The utility model provides a beam bending deformation experiment teaching aid which comprises a beam fixing frame, a data acquisition device and a computer system with built-in LabView software, wherein a cantilever beam sample is fixed on the beam fixing frame, a bending deformation measuring module is arranged on the cantilever beam sample, the bending deformation measuring module is fixed on the beam fixing frame and is electrically connected with the data acquisition device, and the data acquisition device inputs acquired data information into the computer system for data analysis and data storage and displays the acquired data information through the computer system. The utility model further comprises a strain acquisition instrument and a bending stress measurement module, wherein the bending stress measurement module is arranged on the upper surface or/and the lower surface of the cantilever beam sample and is electrically connected with the strain acquisition instrument. According to the utility model, the course theory and the experimental model can be in seamless joint, so that students can recognize and understand the experimental measurement principle, the measurement process and the method of the beam bending deformation and the difference between experimental data and theoretical calculation, and the cognitive level of the students on the theory related to the material bending deformation can be enhanced.

Description

Bending deformation experiment teaching aid for beam

Technical Field

The utility model relates to a mechanical property detection experiment teaching aid, in particular to an experiment teaching aid for demonstrating and verifying a beam bending deformation related theory.

Background

In the courses of engineering mechanics widely opened in the academy of engineering, the bending theory of the beam is the most complex of four internal force states, and the calculation of the bending deformation part is a difficult point in the bending theory of the beam. For ease of understanding, a relatively simple cantilever beam model is generally selected for introduction in the teaching material. However, the beam bending theory experiment teaching aid sold in the domestic market at present adopts a simply supported beam model, but cannot form one-to-one correspondence with theory introduction in teaching materials, so that the learning intensity of students is further increased, and the comparison and verification of the beam bending deformation theory cannot be realized, so that the fundamental purpose of experimental teaching is lost.

At present, related teaching aids sold in domestic markets are non-matched simply supported beam models, and parameter measurement modes can be generally divided into two types. The first type of related components which are not matched for measuring bending deformation and bending stress are required to be designed and installed by themselves, and the measuring precision cannot be ensured; the second category integrates measuring means, but can only measure parameters at a fixed location, without expansibility. The experimental data collected once under the design is limited, repeated experiments are needed to be carried out for many times in a strict sense, and resources are wasted; meanwhile, the experimental result cannot be used for verifying the predicted result of the theory because the integral change trend of the beam cannot be observed, so that the meaning of the theory on the actual guidance cannot be displayed, and the defects of the theory are discussed, so that the follow-up expansion is performed.

Meanwhile, the existing beam bending test bed adopts dial indicator/dial indicator reading to measure the deflection value of the beam, and the measurement accuracy is enough but belongs to traditional mechanical measurement, and is not easy to maintain. And the measurement precision, stability, reliability and the like are weaker than those of the novel electrification measurement mode.

Therefore, it is necessary to solve the above-described drawbacks.

Disclosure of Invention

The utility model aims to provide a beam bending deformation experiment teaching aid matched with teaching materials.

The utility model provides a beam bending deformation experiment teaching aid, which comprises a beam fixing frame, a data acquisition device and a computer system, wherein LabView software is arranged in the computer system, a cantilever beam sample is fixed on the beam fixing frame, a bending deformation measuring module is arranged on the cantilever beam sample, the bending deformation measuring module is fixed on the beam fixing frame and is electrically connected with the data acquisition device, and the data acquisition device inputs acquired data information into the computer system for data analysis and data storage and displays the acquired data information through the computer system.

Optionally, the bending deformation measurement module is at least one displacement sensor.

Optionally, the device further comprises a strain acquisition instrument and a bending stress measurement module, wherein the bending stress measurement module is arranged on the upper surface or/and the lower surface of the cantilever beam sample and is electrically connected with the strain acquisition instrument, and the strain acquisition instrument is used for acquiring and displaying the strain value of the cantilever beam sample under the action of load.

Optionally, the bending stress measurement module is at least one strain gauge.

Optionally, the beam fixing frame comprises a supporting piece and at least one positioning clamp, one end of the cantilever beam sample is fixed on the supporting piece, and the other end is hung with a load; the positioning clamp is used for installing the bending deformation measuring module, is fixed on the supporting piece or movably fixed on the supporting piece and is correspondingly arranged above the cantilever beam sample, so that the bending deformation measuring module is arranged at the measuring position of the cantilever beam sample.

Optionally, the supporting piece includes fixed plate and bearing, the fixed plate level sets up, the one end of fixed plate is installed on the bearing, and the other end outwards extends, set up a plurality of mounting holes on the fixed plate for with the positioning fixture is connected.

Optionally, the supporting seat is composed of a bottom plate and a supporting plate, the bottom plate is horizontally arranged, the supporting plate is vertically arranged on the bottom plate, the bottom end of the supporting plate is fixed at one end of the bottom plate, and the top end of the supporting plate is fixed at one end of the fixing plate, so that the bottom plate, the supporting plate and one end of the fixing plate form a frame-shaped structure.

Optionally, the positioning fixture includes a base body, a central hole for clamping the bending deformation measurement module is formed in the base body, one end of the base body is fixed on the supporting piece, the other end of the base body is a free end extending outwards, the free end is provided with an opening through slot leading to the central hole, and a through hole penetrates through the opening through slot along the transverse direction of the opening through slot.

The utility model has the following technical effects:

(1) The utility model can intuitively and clearly display the deformation process and the stress condition of the cantilever beam during the bending experiment, can intuitively display the basic knowledge points such as the bending deformation trend, the bending stress distribution characteristics and the like of the beam under load, is convenient for students to observe, understand and master the bending deformation process and the principle of the cantilever beam, has good demonstration effect, and can help the students to better understand the related theory of the bending deformation of the material.

(2) According to the utility model, the cantilever beam is built by adopting the beam fixing frame, and the bending deformation measuring module, the bending stress measuring module, the data acquisition device and the computer system are matched, so that students can acquire parameters of a plurality of positions in one experiment, draw a deformation trend curve and a theoretical prediction curve for comparison, and intuitively feel the difference between a real result and theoretical analysis.

(3) In the measurement link of the experiment, the traditional measurement tool reading is replaced by adopting the computer-based electrical measurement, so that the measurement precision can be improved, the influence of measurement errors on the experimental result is reduced, and the acceptance of students on the experimental result and course theory is enhanced; the method also trains the capability of students to realize man-machine interaction by programming, is a process of linking computer programming theory in learning class with industrial application, and can play a role of a bridge. Most importantly, the implementation process gives students the opportunity to contact related equipment and underlying principles and operation modes in advance, and is helpful for improving future employment competitiveness.

(4) The utility model is easy to install and fix, convenient for students to operate and use, has real effect and can assist in improving teaching quality.

Drawings

FIG. 1 is a schematic representation of an embodiment of the present utility model;

FIG. 2 is a schematic view of a cantilever beam specimen mounted on a beam mount according to an embodiment of the present utility model;

FIG. 3 is a schematic view of a beam holder according to an embodiment of the present utility model;

fig. 4 is a schematic structural view of a positioning fixture according to an embodiment of the present utility model.

Detailed Description

The present utility model will be described in further detail with reference to the following examples in order to make the objects, technical solutions and advantages of the present utility model more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the utility model.

It will be understood that when an element is referred to as being "connected," "disposed," or "disposed" on another element, it can be directly on the other element or intervening elements may also be present.

It should be further noted that, in the embodiments of the present utility model, the terms of "one end" and "the other end" are merely relative concepts or references to the normal use state of the product, or references to the positions shown in the drawings, merely for convenience in describing the present utility model and simplifying the description, and do not indicate or imply that the apparatus or element to be referred to must have a specific orientation, be configured and operated in a specific orientation, and should not be considered as limiting.

Referring to fig. 1-2, the beam bending deformation experiment teaching aid provided by the utility model comprises a data acquisition device 1, a computer control system 2 and a beam fixing frame 6, wherein a cantilever beam sample 8 for a test experiment is fixed on the beam fixing frame 6, one end of the cantilever beam sample 8 is provided with a load 9, and the length direction of the cantilever beam sample 8 is provided with at least one bending deformation measuring module 5 for measuring the bending deformation amount generated when the cantilever beam sample 8 loads the load 9. The bending deformation measuring module 5 is fixed on the beam fixing frame 6 and is electrically connected with the data acquisition device 1, and the data acquisition device 1 can input data information of the bending deformation measured by the bending deformation measuring module 8 into the controller computer system 2 for analysis and processing. The computer system 2 is internally provided with LabView software, in teaching, an operator manually builds the LabView program, and correct displacement readings measured by the bending deformation measuring module 5 are corrected and output through a test piece with standard thickness. LabView software can perform data analysis and data storage on the acquired bending deformation, and display the acquired bending deformation on a display in the computer system 2 through a graph, so that students can intuitively feel the overall change trend of the beam in the bending deformation experimental process while training the capacity of realizing man-machine interaction by programming, and the differences of the beam bending deformation experimental measurement principle, the measurement process and method and experimental data and theoretical calculation analysis are recognized and understood. The experiment teaching aid can be used for seamlessly butting course theory and experiment, and can enhance the cognitive level of students on the theory related to material bending deformation.

The bending deformation measuring module 5 is a displacement sensor, is arranged on the cantilever beam sample 8, and is used for measuring the bending deformation of the cantilever beam sample 8 after loading, converting the mechanical displacement of a measuring point when the cantilever beam sample 8 is bent and deformed into an electric signal which is in linear or arbitrary functional relation with the electric signal, outputting the electric signal to the data acquisition device 1, storing and processing the electric signal acquired in real time by the data acquisition device 1, sending the electric signal into the computer system 2 through a USB interface, and measuring and processing the electric signal by adopting pre-compiled LabView software in the computer system 2. In the embodiment of the utility model, 4 displacement sensors are selected and distributed on the cantilever beam sample 8.

Referring to fig. 1 and 2, the present utility model further includes a strain gauge 4 and a bending stress measuring module 7, wherein the bending stress measuring module 7 is disposed on the upper surface or/and the lower surface of the cantilever beam sample 8, and the bending stress measuring module 7 is electrically connected with the strain gauge 4. The bending stress measuring module 7 can adopt strain gauges, and can adopt 2-4 strain gauges, and is pre-attached to the upper surface or/and the lower surface of the cantilever beam sample 8. When the cantilever beam sample 8 is mechanically deformed under the action of the load 9, the sensitive grid on the strain gauge deforms along with the mechanical deformation to change the resistance of the mechanical deformation, the change is transmitted to the strain acquisition instrument 4 through a signal, the strain acquisition instrument 4 can directly display the strain value of the measuring position of the cantilever beam sample 8, draw a time domain curve in real time, and can also transmit data information acquired in real time to the data acquisition instrument 1 to be input into the computer system 2 for analysis and processing. In the course, students can learn how to acquire strain and stress using the strain gauge 4 system and understand the working principle and operation of the strain gauge and the strain gauge 4.

Referring to fig. 2-4, the beam holder 6 includes a support 61 and at least one positioning jig 62, one end of the cantilever beam specimen 8 is fixed to the support 61, and is located at the lower end of the support 61, and the other end of the cantilever beam specimen 8 is a free end, on which the load 9 is hung. During course teaching, an operator can suspend different loads 9 at the free end of the cantilever beam sample 8, and the bending deformation of the cantilever beam sample 8 under the different loads 9 is demonstrated. The positioning clamp 62 is used for installing the positioning bending deformation measuring module 5, and the positioning clamp 62 is correspondingly arranged above the cantilever beam sample 8, so that the positioning bending deformation measuring module 5 is positioned at the measuring position of the cantilever beam sample 8 through the clamping of the positioning clamp 62. The positioning fixture 62 can be directly fixed on the supporting piece 61 according to experimental requirements, and the positioning fixture 62 can be fixed after moving relative to the supporting piece 61 so as to adapt to the requirements of different measuring positions and different types of bending deformation measuring modules 5 on different cantilever beam samples 8.

Referring to fig. 2 and 3, the support 61 includes a support block 612 and a fixing plate 611, and one end of the cantilever beam sample 8 is fixed to the support block 612. The fixing plate 611 is horizontally disposed, and a plurality of mounting holes 6111 are formed on one side surface thereof for connection with each positioning jig 62. The mounting holes 6111 are arranged on the fixing plate 611 in multiple points, so that each positioning clamp 62 can select different mounting holes 6111 to be connected and fixed with the fixing plate 611 according to the measuring position of the cantilever beam sample 8, and the distribution position of the bending deformation measuring module 5 can be determined by adjusting the positions of the positioning clamps 62, so that the bending deformation measuring module is convenient and flexible. The fixing plate 611 is an L-shaped plate with a protruding structure at one side, and the protruding part is used for being connected with the supporting seat 612, so that the fixing plate 611 is fixed on the supporting seat 612 in a cantilever manner, and is consistent with the installation manner of the cantilever beam sample 8 on the supporting seat 612, thereby facilitating the installation of the positioning clamp 62. It should be understood that the movable fixing of the positioning fixture 62 on the fixing plate 611 may take many forms, and it is within the scope of the present utility model to conveniently and flexibly adjust the mounting position of the positioning fixture 62 on the fixing plate 611.

The supporting seat 612 is composed of a bottom plate 6121 and a supporting plate 6122, the bottom plate 6121 is horizontally arranged and can be fixed on a table top, the supporting plate 6122 is vertically arranged, one end of the supporting plate 6122 is fixed on the bottom plate 6121, the other end of the supporting plate is connected with the protruding part of the fixing plate 611, one end of the fixing plate 611 is arranged on the supporting plate 6122, and the other end of the fixing plate 611 extends outwards to form a cantilever mode for installing the positioning clamp 62. In the above-mentioned structure of the supporting seat 612, one ends of the bottom plate 6121, the supporting plate 6122 and the fixing plate 611 may form a frame structure. During teaching demonstration, the bottom plate 6121 can be directly fixed on the demonstration table surface, and the demonstration table is fixed by using a fastener, or the frame-shaped structure formed by the bottom plate 6121, the supporting plate 6122 and the fixing plate 611 can be clamped and fixed on the table plate of the demonstration table, so that the demonstration table is very convenient.

Referring to fig. 2 and 4, the positioning fixture 62 includes a base 621, a central hole 622 is formed in the base 621, and is used for clamping the bending deformation measuring module 5, one end a of the base 621 passes through a mounting hole 6111 in the fixing plate 611, and a positioning pin at a horizontal position, and is fixed to the fixing plate 611 in a two-point manner, and the other end is a free end B extending outwards, the free end B has an open through slot 623, and the outermost end along the free end B is led to the central hole 622. A through hole 624 is formed in the free end B of the base 621 in a lateral direction of the open through groove 623. Grooves 625 are also machined inward on both sides of the base 621 to reduce the thickness on both sides of the central aperture 622. When the bending deformation measuring module 5 is placed on the central hole 622, a fastener (such as a bolt) can be inserted into the through hole 624 (not shown) to be screwed, so that the two sides of the central hole 622 are slightly deformed, the width of the open through groove 623 is reduced, and thus the bending deformation measuring module 5 can be tightly clamped and fixed on the positioning fixture 62, and the whole displacement of the bending deformation measuring module 5 when the cantilever beam sample 8 is loaded is avoided. It will be appreciated that the positioning fixture 62 of the present utility model may also adopt a similar clip structure as described above, and it is within the scope of the present utility model as long as the bending deformation measuring module 5 can be movably mounted and fastened to the positioning fixture 62.

Referring to fig. 1, the present utility model further provides a power supply device 10 for supplying power to the computer system 2, the strain gauge 4, the data collector 1, the bending deformation measuring module 5 and the bending stress measuring module 7.

The computer system 2 may also be connected to a printer 3, and may output the experimental results in the form of text.

The above-described embodiments of the present utility model are only some of the preferred embodiments of the present utility model and are not intended to limit the present utility model, and any modifications, equivalent substitutions and improvements made by those skilled in the art without departing from the spirit of the present utility model shall fall within the scope of the present utility model.

Claims

1. The utility model provides a bending deformation experiment teaching aid of roof beam, its characterized in that, includes roof beam mount, data acquisition ware and computer system, computer system embeds LabView software, be fixed with the cantilever beam sample on the roof beam mount, be equipped with bending deformation's measurement module on the cantilever beam sample, bending deformation measurement module fixes on the roof beam mount and with the data acquisition ware electricity is connected, data acquisition ware will the data information input of gathering computer system carries out data analysis and data storage, and through computer system shows.

2. The beam bending deformation test teaching aid according to claim 1, wherein the bending deformation measurement module is at least one displacement sensor.

3. The beam bending deformation experiment teaching aid according to claim 1, further comprising a strain acquisition instrument and a bending stress measurement module, wherein the bending stress measurement module is arranged on the upper surface or/and the lower surface of the cantilever beam sample and is electrically connected with the strain acquisition instrument, and the strain acquisition instrument is used for acquiring and displaying a strain value of the cantilever beam sample under the action of load.

4. A beam bending deformation test teaching aid according to claim 3 and wherein said bending stress measurement module is at least one strain gauge.

5. A beam bending deformation test teaching aid according to any of claims 1-4 and wherein said beam holder comprises a support member and at least one positioning clamp, said cantilever beam specimen being secured at one end to said support member and a load being suspended at the other end; the positioning clamp is used for installing the bending deformation measuring module, is fixed on the supporting piece or movably fixed on the supporting piece and is correspondingly arranged above the cantilever beam sample, so that the bending deformation measuring module is arranged at the measuring position of the cantilever beam sample.

6. The teaching aid for beam bending deformation experiments according to claim 5, wherein the supporting member comprises a fixing plate and a supporting seat, the fixing plate is horizontally arranged, the fixing plate is installed on the supporting seat in a cantilever mode, the other end of the fixing plate extends outwards, and a plurality of installation holes are formed in the fixing plate and are used for being connected with the positioning clamp.

7. The teaching aid for beam bending deformation experiments according to claim 6, wherein the supporting base is composed of a base plate and a supporting plate, the base plate is horizontally arranged, the supporting plate is vertically arranged on the base plate, the bottom end of the supporting plate is fixed at one end of the base plate, and the top end of the supporting plate is fixed at one end of the fixing plate, so that the base plate, the supporting plate and one end of the fixing plate form a frame-shaped structure.

8. A beam bending deformation test teaching aid according to claim 5 and characterized in that said positioning fixture comprises a base body provided with a central hole for clamping said bending deformation measuring module, said base body being secured at one end to said support member and at the other end being an outwardly extending free end having an open channel opening into said central hole, and a through hole extending transversely of said open channel.