CN214796424U

CN214796424U - Mechanics experimental apparatus based on singlechip

Info

Publication number: CN214796424U
Application number: CN202120817470.2U
Authority: CN
Inventors: 孙尚宇
Original assignee: Individual
Current assignee: Individual
Priority date: 2021-04-21
Filing date: 2021-04-21
Publication date: 2021-11-19
Anticipated expiration: 2031-04-21

Abstract

The utility model discloses a mechanics experimental apparatus based on singlechip relates to physics mechanics experiment technical field, has solved the unable digital demonstration of mechanics experimental apparatus, interesting relatively poor technical problem. The device comprises a force sensor, a singlechip and a display module; the force sensors comprise strain resistance discs and cantilever beams, and the strain resistance discs are fixed on two sides of the cantilever beams; when the stressed object is stressed, the cantilever beam and the strain resistance chip deform, and the analog voltage signal output by the driving sensor synchronously changes; the analog voltage signal is amplified and AD converted to obtain a digital voltage signal, the digital voltage signal is input into the single chip microcomputer, and the single chip microcomputer processes the digital voltage signal to generate a stress numerical value of the cantilever beam; the display module displays the stress numerical value. The utility model discloses not only realize also having increased the interest to the digital measurement of power in the physical experiment.

Description

Mechanics experimental apparatus based on singlechip

Technical Field

The utility model relates to a physics mechanics experiment technical field especially relates to a mechanics experimental apparatus based on singlechip.

Background

When middle school learns the physical mechanics, the middle school can have corresponding physical experiments to assist students to understand and learn the physical mechanics more quickly. In an experiment, some instruments are usually required to complete the experiment. A simple interesting experimental apparatus not only can mobilize the teaching enthusiasm of teachers, but also can enable students to enjoy the interest of doing experiments in the process of doing experiments. For example, in the study of the pressure or the tensile force, the change of the pressure or the tensile force in various physical states needs to be intuitively studied by a mechanical experiment device, and thus the pressure or the tensile force needs to be measured.

In the prior art, the mechanical experiment device mainly tests the stress of an object through the spring chest expander, cannot digitally demonstrate and is relatively poor in interestingness.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a mechanics experimental apparatus based on singlechip to solve the mechanical experimental apparatus that exists among the prior art and mainly test the atress that the object received through the spring chest expander, unable digital demonstration, interesting relatively poor technical problem. The utility model provides a plurality of technical effects that preferred technical scheme among a great deal of technical scheme can produce see the explanation below in detail.

In order to achieve the above purpose, the utility model provides a following technical scheme:

the utility model provides a mechanics experimental apparatus based on single chip microcomputer, which comprises a force sensor, a single chip microcomputer and a display module; the single chip microcomputer is electrically connected with the force sensor and the display module; the force sensor comprises a strain resistance chip and a cantilever beam, wherein the strain resistance chip is fixed on two sides of the cantilever beam; the cantilever beam is connected with a stressed object; when the stressed object is stressed, the cantilever beam and the strain resistance chip deform to drive the analog voltage signal output by the force sensor to change synchronously; the analog voltage signal is amplified and AD converted to obtain a digital voltage signal, the digital voltage signal is input into the single chip microcomputer, and the single chip microcomputer processes the digital voltage signal to generate a stress numerical value of the cantilever beam; and the display module displays the stress numerical value.

Preferably, the strain resistance sheet comprises four variable resistors and constitutes a Wheatstone bridge circuit.

Preferably, two of the variable resistors in the strain resistor disc are fixed to one side of the cantilever beam, and the other two variable resistors are fixed to the other side of the cantilever beam.

Preferably, the strain resistance sheet and the cantilever beam are fixed in a gluing mode and sealed through glue.

Preferably, the both ends of cantilever beam are atress end and stiff end respectively, the atress end is unsettled, the direction of force with the atress end is perpendicular, the stiff end is fixed with the bottom plate.

Preferably, the mechanics experimental apparatus still includes voice module, voice module with the single chip microcomputer electricity is connected, can with atress numerical value converts the pronunciation into to report through loudspeaker.

Preferably, the mechanics experimental apparatus further comprises an alarm module, wherein the alarm module is electrically connected with the single chip microcomputer and alarms through a buzzer.

Preferably, the mechanical experiment device further comprises a signal amplifying and AD converting circuit, the signal amplifying and AD converting circuit is connected with the output end of the wheatstone bridge circuit, and the analog voltage signal passes through the signal amplifying and AD converting circuit to obtain a digital voltage signal.

Preferably, the single chip microcomputer is an STM series or 51 series single chip microcomputer, and the signal amplification and AD conversion circuit adopts any one of an HX711 chip, an AD7190 chip and an AD7714 chip.

Preferably, the force sensor is a pressure sensor and/or a tension sensor.

Implement the utility model discloses a technical scheme among the above-mentioned technical scheme has following advantage or beneficial effect:

the utility model discloses a measurement of force is carried out in the cooperation of resistance card and cantilever beam to meeting an emergency, and the analog voltage signal that resistance card produced behind the atress deformation sends the singlechip to after handling this signal, converts this signal processing into atress numerical value through the singlechip to demonstrate through display module. Not only completes the measurement of the traditional experimental device on the force (such as pressure, pulling force, gravity and the like), but also increases the interest and novelty of the experiment.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained without inventive work, and in the drawings:

fig. 1 is a schematic block diagram of an embodiment of the mechanical experiment device based on the single chip microcomputer of the present invention;

fig. 2 is a schematic view of a strain gauge according to an embodiment of the present invention;

fig. 3 is a schematic view of the cantilever beam fixing according to the embodiment of the present invention;

fig. 4 is a schematic diagram of a strain gauge connection according to an embodiment of the present invention;

fig. 5 is the internal structure diagram of HX711 chip in the embodiment of the present invention;

fig. 6 is a circuit diagram of the AD conversion module of the HX711 chip according to the embodiment of the present invention.

In the figure: 1. a strain resistance chip; 2. a wire; 3. a cantilever beam; 4. a base plate; 5. a connecting member; 6. and (4) screws.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, various exemplary embodiments to be described below will refer to the accompanying drawings, which form a part hereof, and in which are described various exemplary embodiments that may be employed to implement the present invention. The same numbers in different drawings identify the same or similar elements unless otherwise indicated. The implementations described in the exemplary embodiments below are not intended to represent all implementations consistent with the present disclosure. It is to be understood that they are merely examples of processes, methods, apparatus, etc., consistent with certain aspects of the present disclosure, as detailed in the appended claims, and that other embodiments may be used or structural and functional modifications may be made to the embodiments set forth herein without departing from the scope and spirit of the present disclosure.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," and the like are used in the orientations and positional relationships illustrated in the accompanying drawings for convenience in describing the present invention and for simplicity in description, and do not indicate or imply that the elements so referred to must have a particular orientation, be constructed and operated in a particular orientation. The terms "first", "second", etc. are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. The term "plurality" means two or more. The terms "connected" and "coupled" are to be construed broadly and may include, for example, a fixed connection, a removable connection, an integral connection, a mechanical connection, an electrical connection, a communicative connection, a direct connection, an indirect connection via intermediate media, and may include, for example, a connection between two elements or an interaction between two elements. The term "and/or" includes any and all combinations of one or more of the associated listed items. The specific meaning of the above terms in the present invention can be understood according to specific situations by those skilled in the art.

In order to explain the technical solution of the present invention, the following description is made by way of specific examples, and only the portions related to the embodiments of the present invention are shown.

The first embodiment is as follows:

as shown in fig. 1-6, the utility model provides a mechanics experimental apparatus based on singlechip, including force sensor, singlechip and display module, the singlechip is connected with force sensor, display module electricity, can realize data and signal transmission each other. The force sensor is used for sensing pressure, tension, gravity and the like in a mechanics experiment and comprises a strain resistance chip 1 and a cantilever beam 3, wherein the strain resistance chip 1 is fixed on two sides of the cantilever beam 3, and the cantilever beam 3 is made of a force-sensitive material and also generates larger deformation under the action of smaller tension or elasticity, so that the corresponding stress value can be conveniently measured. The cantilever beam 3 is connected with the stressed object to realize the support and fixation of the stressed object. When the stressed object is stressed, the cantilever beam 3 and the strain resistance chip 1 deform, and the analog voltage signal output by the driving force sensor changes synchronously. The analog voltage signal is amplified and AD converted to obtain a digital voltage signal, the digital voltage signal is input into the single chip microcomputer, the single chip microcomputer can directly process the digital voltage signal, the single chip microcomputer processes the digital voltage signal to generate a stress numerical value of the cantilever beam 3, and the stress numerical value is a pressure, tension or gravity numerical value measured by a mechanical experiment. The display module displays the stress numerical value. Specifically, the display module is liquid crystal display, and LCD1602 is adopted to the model, and the display module transmits the atress data that the singlechip produced for LCD1602 liquid crystal display to show on LCD1602 liquid crystal display, the atress size of the atress object that can audio-visual demonstration is measured. The utility model discloses a measurement of force is carried out in the cooperation of resistance card 1 and cantilever beam 3 that meets an emergency, and resistance card 1 produces corresponding analog voltage signal after the atress deformation, sends the singlechip to after this signal processing, and the singlechip converts this signal processing into atress numerical value to demonstrate through display module. Not only the measurement of the traditional experimental device on the pressure and the tension is completed, but also the interest and the novelty of the experiment are increased.

As an alternative embodiment, as shown in fig. 4, the strain resistance sheet 1 includes four variable resistors and constitutes a wheatstone bridge circuit. Specifically, 4 strain resistance card 1 constitute the wheatstone bridge circuit, namely full-bridge bleeder circuit, and when any one strain resistance card 1 atress changes, the resistance of strain resistance card 1 changes and changes into the change of voltage output, can change the physical quantity of atress size into voltage output quantity through strain resistance card 1, through measuring the numerical value of output voltage, the size of the power that just can be measured through the conversion, the initial resistance of variable resistance all prefers 1K ohm, the resistance is selected 1K ohm and is convenient for calculate when the resistance changes. The E + and E-of the Wheatstone bridge circuit are respectively connected with the positive pole and the negative pole of the excitation voltage through leads 2, and the S + and S-are respectively connected with the positive pole and the negative pole of the power voltage through leads 2.

As an alternative embodiment, as shown in fig. 2, two variable resistors (R1 and R4) in the strain resistance sheet 1 are fixed on one side of the cantilever beam 3, and the other two variable resistors (R2 and R3) are fixed on the other side of the cantilever beam 3; specifically, the strain resistance chip 1 is fixed on the upper side and the lower side of the cantilever beam 3 in a sticking mode, the strain resistance chip 1 is a thin sheet, and the strain resistance chip 1 is fixed and ensured to deform together with the cantilever beam 3 under the action of external force through glue sticking, for example, when pressure is collected, the strain resistance chip 1 on the upper side is stressed and stretched, and the strain resistance chip 1 on the lower side is stressed and stretched. The strain resistance chip 1 is sealed by glue; specifically, if seal through hot melt adhesive etc. and seal through gluing, can completely cut off the contact of air and resistance card 1 that meets resistance card 1 to insulating nature's requirement, reduce the influence of external factor to resistance.

As an alternative embodiment, as shown in fig. 2 to 3, two ends of the cantilever beam 3 are respectively a stressed end and a fixed end, the stressed end is suspended, and the fixed end is fixed with the base plate 4. When the stress end is suspended to enable the cantilever beam 3 to deform, the cantilever beam 3 cannot influence the accuracy of an experimental result and cannot generate measurement errors due to the fact that the cantilever beam 3 is in contact with the bottom plate 4 to influence normal deformation. When measuring the pressure, as shown in fig. 3, the pressure can be fixed, when testing the pulling force, the friction force can be measured in the same way as the pulling force when the stressed object moves at a uniform speed, the direction shown in fig. 3 can be rotated by 90 degrees for fixing, and the cantilever beam 3 can be provided with a through hole for fixing a string and the like when testing the pulling force. The direction of the force is vertical to the stress end, so that the corresponding pressure or tension applied to the object can be accurately measured, and the influence of the component force on the accuracy of the measurement result is avoided. The fixed end can be fixed on the bottom plate 4 through a screw 6, a connecting piece 5 and the like, the connecting piece 6 has certain thickness, and suspension of the stress end of the cantilever beam 3 is achieved, and the force sensor is integrally fixed.

As an optional implementation mode, the mechanical experiment device further comprises a voice module, the voice module is electrically connected with the single chip microcomputer, the stress numerical value can be converted into voice, and the voice can be broadcasted through a loudspeaker. Specifically, the atress numerical value that the singlechip generated converts the pronunciation for text signal through voice module, and loudspeaker come out the voice broadcast of conversion, and language module reports the interest that the experimental result further promoted the device.

As an optional implementation mode, the mechanical experiment device further comprises an alarm module, and the alarm module is electrically connected with the single chip microcomputer and gives an alarm through a buzzer. Specifically, the buzzer adopts a DC5V active buzzer, and when the single chip microcomputer detects that the stress exceeds the limit (the specific numerical value is determined by the cantilever beam 3 and the strain resistance sheet 1, and can be set individually according to different devices), the buzzer is triggered, so that the force sensor is protected. As shown in FIG. 1, the power supply system of the experimental device adopts a direct current power supply, preferably a 19V direct power supply machine, and simultaneously converts the direct current power supply into 5V power through a DC-DC module and supplies the 5V power to a single chip microcomputer. The motor can generate pulling force or pressure through a ball screw and other mechanisms and act on the force sensor, so that uniform force output is generated conveniently.

As an optional implementation mode, the mechanical experiment device further comprises a control key, and the control key is used for turning on or off the voice broadcast and the motor, so that more various functions of the device are realized.

As an optional implementation manner, as shown in fig. 1, the mechanical experiment device further includes a signal amplifying and AD converting circuit, where the signal amplifying and AD converting circuit is connected to an output end of the wheatstone bridge circuit, so that the wheatstone bridge circuit inputs an analog voltage signal with a voltage change into the signal amplifying and AD converting circuit, the analog voltage signal obtains a digital voltage signal through the signal amplifying and AD converting circuit, and the single chip microcomputer receives the digital voltage signal and then converts the voltage signal into a stress value through calculation.

As an optional implementation manner, the single chip microcomputer is an STM series or 51 series single chip microcomputer, and the signal amplification and AD conversion circuit adopts any one of an HX711 chip, an AD7190 chip, and an AD7714 chip. Preferably, the single chip microcomputer is an MCU of STC89C52RC or the like, and the signal amplifying and AD converting circuit adopts an HX711 chip or a similar high-precision AD chip. STC89C52RC is a basic and common 51-series single-chip microcomputer, has stable and reliable performance, and is convenient to purchase and reduce the cost of the device. As shown in fig. 5, the HX711 chip is a 24-bit AD converter chip specially designed for high-precision electronic scales, and integrates peripheral circuits required by other chips of the same type, such as a regulated power supply, an on-chip clock oscillator, and the like, and has the advantages of high integration level, high response speed, strong interference resistance, and the like. The interface and programming of the chip and the single chip are very simple, all control signals are driven by pins, and registers in the chip do not need to be programmed. The input selection switch can arbitrarily select the channel A or the channel B and is connected with the low-noise programmable amplifier inside the input selection switch. As shown in fig. 6, U4 is the HX711 chip, pin 16 of U4 is connected to VCC, pins 14 and 15 are connected to a common ground, pin 2 is a BASE pin which is an external regulated power output control terminal, and AVDD is an external regulated power output and is used to provide an excitation regulated power for the strain resistance sensor, wherein a regulated output value of the AVDD voltage is determined by resistors R12 and R13, and the AVDD output regulated value is calculated as follows: v (avdd) ═ v (vbg) (R12+ R13)/R13. Where V (vbg) is a reference voltage, the value of which is 1.265V, the resistance of the resistor R12 is 20K, and the resistance of the resistor R13 is 8.2K, and the above calculation formula is substituted to obtain V (avdd) ═ 1.265(20+8.2)/8.2 ═ 4.35V, which is the excitation voltage of the strain resistance chip 1. The

pins

7 and 8 of the U2 are input ports of A channel, the

pins

9 and 10 are input ports of B channel, and the RC filter circuit formed by the resistors R8 and C4, R9 and C5 is used for realizing the filtering function of signals. JC9 terminal is and the connecting terminal between the singlechip, wherein 1 foot connects VCC, 2 feet and 3 feet connect 2 group IO ports of singlechip respectively, JC8 terminal is the terminal that connects resistance card 1, E + and E-connect excitation voltage's positive pole and negative pole respectively, A-and A + connect the A passageway of 711 chip, B-and B + connect the B passageway of 711 chip, the utility model discloses well force transducer adopts the A passageway when the hardware is connected for the sensor all the way, and the unsettled processing is done to the B passageway.

As an alternative embodiment, as shown in fig. 1, the force sensor is a pressure sensor and/or a tension sensor, and the pressure and the tension can be measured separately or together.

The embodiment is only a specific example and does not indicate that the present invention is implemented in such a manner.

While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the spirit and scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, the present invention is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of the present application belong to the protection scope of the present invention.

Claims

1. A mechanics experimental device based on a single chip microcomputer is characterized by comprising a force sensor, the single chip microcomputer and a display module; the single chip microcomputer is electrically connected with the force sensor and the display module;

the force sensor comprises a strain resistance chip and a cantilever beam, wherein the strain resistance chip is fixed on two sides of the cantilever beam; the cantilever beam is connected with a stressed object; when the stressed object is stressed, the cantilever beam and the strain resistance chip deform to drive the analog voltage signal output by the force sensor to change synchronously;

the analog voltage signal is amplified and AD converted to obtain a digital voltage signal, the digital voltage signal is input into the single chip microcomputer, and the single chip microcomputer processes the digital voltage signal to generate a stress numerical value of the cantilever beam;

and the display module displays the stress numerical value.

2. A mechanical experiment device based on a single chip microcomputer according to claim 1, wherein the strain resistance sheet comprises four variable resistors and forms a wheatstone bridge circuit.

3. The single chip microcomputer based mechanical experiment device according to claim 2, wherein two of the variable resistors in the strain resistor discs are fixed to one side of the cantilever beam, and the other two variable resistors are fixed to the other side of the cantilever beam.

4. The mechanical experiment device based on the single chip microcomputer of claim 2, wherein the strain resistance chip and the cantilever beam are fixed in a glued mode and sealed through glue.

5. The mechanical experiment device based on the single chip microcomputer according to claim 2, wherein two ends of the cantilever beam are respectively a stress end and a fixed end, the stress end is suspended, the direction of the force is perpendicular to the stress end, and the fixed end is fixed with the bottom plate.

6. The mechanics experimental apparatus based on singlechip of claim 1, characterized in that, mechanics experimental apparatus still includes voice module, voice module with singlechip electricity is connected, can with atress numerical value converts the pronunciation to report through loudspeaker.

7. The mechanical experiment device based on the single chip microcomputer of claim 1, further comprising an alarm module, wherein the alarm module is electrically connected with the single chip microcomputer and alarms through a buzzer.

8. The single-chip microcomputer based mechanical experiment device according to claim 2, further comprising a signal amplifying and AD converting circuit, wherein the signal amplifying and AD converting circuit is connected to an output end of the wheatstone bridge circuit, and the analog voltage signal passes through the signal amplifying and AD converting circuit to obtain a digital voltage signal.

9. A mechanics experimental apparatus based on singlechip according to claim 8, characterized in that, the singlechip is STM series or 51 series singlechip, and the signal amplification and AD conversion circuit adopts any one of HX711 chip, AD7190 chip, AD7714 chip.

10. A mechanical experiment device based on a single chip microcomputer according to any one of claims 1 to 9, wherein the force sensor is a pressure sensor and/or a tension sensor.