CN206920464U - INTELLIGENT TACHOMETER for Hopkinson pressure bar experiment - Google Patents

Abstract

The utility model discloses a kind of INTELLIGENT TACHOMETER for Hopkinson pressure bar experiment, it is related to velocity measuring device technical field.The tachymeter includes 5V power modules, Laser emission pipe power supply circuit, two LASER Discharge Tubes, startup photoelectric receiving tube, stopping photoelectric receiving tube, pulse shaper, logical circuit of counter circuit, microcontroller, key circuit, display circuit and interface module.The tachymeter can realize testing and control, result show, data storage, distance settings, far-end operation, the function such as test data transmission, improve the workload of the gentle testing efficiency of Automated water of Hopkinson pressure bar experiment, significantly mitigation tester.

Description

INTELLIGENT TACHOMETER for Hopkinson pressure bar experiment

Technical field

It the utility model is related to velocity measuring device technical field, more particularly to it is a kind of for Hopkinson pressure bar experiment INTELLIGENT TACHOMETER.

Background technology

Hopkinson pressure bar experiment is a kind of effective method for testing multiple material mechanical response under high strain-rate, The velocity test for wherein launching compressed air gun trip rod is an important test content in the experiment.To trip rod speed Measurement use source of parallel light velocimetry, as shown in figure 1, be equipped with a parallel laser light source between transmitting tube and incident bar, For launching and receiving laser signal, the spacing between two light sources can set and measure, when trip rod passes through directional light During source, optical signal can be sheltered from and produce the pulse signal of one fixed width, can measure accordingly trip rod by source of parallel light when Between, you can obtain the stroke speed of trip rod.

Current existing Hopkinson pressure bar experiment device speed instrument has the disadvantage that：Start, stop timing signal Pulse shaper is formed using integrated comparator, and bandwidth is inadequate, and caused pulse rise time is long, causes to test instrument meter Number circuit triggering is unreliable；Time-measuring gauge does not have computing function, only has clocking capability, it is impossible to trip rod speed is directly calculated and be shown Degree；Display is charactron, is only able to display numeral, can not show instrument state, the operation prompt information of complexity, cause operation not Just, instrument self checking and fault location function can not be realized；The automatic storage and upload of test data can not be realized, is surveyed each time Examination is required for operating personnel to record test data, calculates velocity of shot, is then manually entered computer and is achieved；Timing circuit Using 74 serial small scale integrations compositions, cause that pcb board size is big, and count frequency is low, poor anti jamming capability, logical circuit of counter Easily go wrong, timing logic circuit topology can not be changed, and circuit function can not realize upgrading；LASER Discharge Tube aging is fast, Change frequent；As shown in figure 1, not having communication interface between time-measuring gauge and data handling system, Hopkinson pressure bar can not be realized Laboratory automation.

Utility model content

Technical problem to be solved in the utility model is to provide a kind of intelligent speed-measuring for Hopkinson pressure bar experiment Instrument, the tachymeter can realize testing and control, result show, data storage, distance settings, far-end operation, test data transmit Etc. function, the gentle testing efficiency of Automated water of Hopkinson pressure bar experiment is improved, mitigates the workload of tester significantly.

In order to solve the above technical problems, technical solution adopted in the utility model is：One kind is used for Hopkinson pressure bar The INTELLIGENT TACHOMETER of experiment, it is characterised in that：Including 5V power modules, Laser emission pipe power supply circuit, two LASER Discharge Tubes, Start photoelectric receiving tube, stop photoelectric receiving tube, be pulse shaper, logical circuit of counter circuit, microcontroller, key circuit, aobvious Show circuit and interface module, the output end of the power module is divided into two-way, the first via and the Laser emission pipe power supply circuit Power input connection, the second tunnel is connected with the power input of the module outside LASER Discharge Tube, for providing work for it Make power supply；The power input of the Laser emission pipe power supply circuit is connected with the power input of the LASER Discharge Tube, is used In providing working power for the LASER Discharge Tube；One LASER Discharge Tube is corresponding with starting photoelectric receiving tube, and another swashs Light-emitting tube is corresponding with stopping photoelectric receiving tube；The photoelectric receiving tube is used for the laser letter for receiving LASER Discharge Tube transmitting Number；The signal input part of the photoelectric receiving tube is connected with the signal input part of the pulse shaper, the shaping pulse The signal output part of circuit is connected with the input of the logical circuit of counter circuit；Crystal oscillator is that the logical circuit of counter circuit carries For work clock；The key circuit is connected with the signal input part of the logical circuit of counter circuit, for inputting control command；Institute State and be bi-directionally connected between logical circuit of counter circuit and microcontroller；The signal output part of the display circuit and the microcontroller connects Connect, for showing the data of microcontroller output；The interface module is bi-directionally connected with the microcontroller, for by the survey Fast instrument connects together with data acquisition processing system, carries out the interaction of data.

Further technical scheme is：The Laser emission pipe power supply circuit includes diode D1-D2 and resistance R, institute The positive pole for stating diode D1 connects+5V power supplys, and the negative pole of the diode D1 is connected with the positive pole of the diode D2, two pole Pipe D2 negative pole is connected through the resistance R with the power input of the LASER Discharge Tube.

Further technical scheme is：Pulse shaper includes two structure identical shaping pulse modules, resistance R1 and resistance R2 node is the signal input part of the shaping pulse module, and a signal of the shaping pulse module inputs End is connected with the colelctor electrode of photoelectric receiving tube one of those described, and the grounded emitter of the photoelectric receiving tube, resistance R1's is another One termination+5V power supplys, resistance R2 other end ground connection, the resistance R1 and resistance R2 node connect with triode Q1 base stage Connect, the colelctor electrode of the triode Q1 connects+5V power supplys, and the emitter stage of the triode Q1 is divided into two-way, and the first via is through resistance R3 Ground connection, the second tunnel are connected with triode Q2 base stage, and a resistance R4 termination+5V power supplys, the resistance R4 other end is divided into two-way, The first via is connected with triode Q3 base stage, and the second tunnel is connected with triode Q2 colelctor electrode, and triode Q2 emitter stage is through electricity Hinder R5 ground connection；The colelctor electrode of the triode Q3 is divided into two-way, and the first via is connected with+5V power supplys, and the second tunnel connects through electric capacity C10 Ground；Triode Q3 emitter stage is divided into two-way, and all the way with the signal output part of the shaping pulse module, another way is through resistance R6 Ground connection.

Further technical scheme is：The logical circuit of counter circuit, which includes starting, stops logic circuit, 20 addition meters Number device, 8 up counters, stop counting interrupt logic circuit, start halted state latch, counter Q19-Q16 latches Device, counter Q15-Q8 latch, counter Q7-Q0 latch, self-test counter Q7-Q0 latch, key-press status latch, Output selection logic circuit and output multi-channel selector；It is described to start the input and shaping pulse electricity for stopping logic circuit The output end connection on road, described start stop the enabling signal output end of logic circuit and are divided into two-way, the first via with described 20 The input connection of up counter, the second tunnel are connected with the input of the startup halted state latch；The startup stops Only the stop signal output end of logic circuit is divided into three tunnels, and the first via is connected with the input of 20 up counters, the second tunnel It is connected with the input for starting halted state latch, the 3rd tunnel is connected with stopping the input of counting interrupt logic circuit, institute The output end for stating stopping counting interrupt logic circuit is interrupt signal output end；The output end for starting halted state latch It is connected with an input of the output multi-channel selector；Clock signal respectively with 20 up counters and 8 The input connection of up counter, reset signal are defeated with 20 up counters and 8 up counters respectively Enter end connection, self-test signal is connected with the input of 8 up counters；Three outputs of 20 up counters End respectively through the counter Q19-Q16 latch, counter Q15-Q19 latch, counter Q7-Q0 latch with it is described Three signal input parts connection of output multi-channel selector；The output end of 8 up counters is through the self-test counter Q7- Q0 latch is connected with the input of the output multi-channel selector, the output end of key circuit and the key-press status latch Input connection, the output end of the key-press status latch is connected with the input of the output multi-channel selector, micro-control The output end of device processed selects logic circuit to be connected with the input of the output multi-channel selector through the output, and the output is more The output end of road selector is connected with the signal input part of the microcontroller.

Further technical scheme is：The logical circuit of counter circuit uses the double D triggerings of 7474 band set-resets just triggering Device, which forms to start, stops logic circuit.

Further technical scheme is：The microcontroller uses STC89C52RC type single-chip microcomputers.

Further technical scheme is：The interface module is serial communication interface module.

Further technical scheme is：The serial communication interface module is RS232 interface module.

Further technical scheme is：The RS232 interface module uses MAX3232 cake cores.

Further technical scheme is：The display circuit uses LCD1602 type LCD MODULEs.

It is using beneficial effect caused by above-mentioned technical proposal：The tachymeter by set data acquisition module with And output transport module, can be achieved testing and control, result show, data storage, distance setting, far-end operation, test data biography The function such as defeated, the gentle testing efficiency of Automated water of Hopkinson pressure bar experiment is improved, mitigate the workload of tester significantly.

Brief description of the drawings

The utility model is described in further detail with reference to the accompanying drawings and detailed description.

Fig. 1 is the structural representation of Hopkinson pressure bar experiment device in the prior art；

Fig. 2 is the theory diagram of tachymeter described in the utility model embodiment；

Fig. 3 is the schematic diagram of laser power supply circuit in the utility model embodiment；

Fig. 4 is the schematic diagram of pulse shaper in the utility model embodiment；

Fig. 5 is the schematic diagram that logic circuit is counted in the utility model embodiment；

Fig. 6 is the schematic diagram for starting, stopping logic circuit in the utility model embodiment；

Fig. 7 is the schematic diagram of microcontroller in the utility model embodiment, display circuit and interface electricity；

Fig. 8 is the main program flow chart that tested the speed in the utility model embodiment；

Fig. 9 is the subroutine flow chart that tested the speed in the utility model embodiment；

Figure 10 is the interface of main menu figure of tachymeter in the utility model embodiment；

Figure 11 is the wait test interface figure of tachymeter in the utility model embodiment；

Figure 12 is the distance setting surface chart of tachymeter in the utility model embodiment；

Figure 13 is tachymeter host computer debugging software main interface figure in the utility model embodiment；

Figure 14 is that tachymeter surveys electronic tag reading surface chart in the utility model embodiment；

Figure 15 is that speedometer distance reads surface chart in the utility model embodiment；

Figure 16 is that speedometer sets surface chart apart from host computer in the utility model embodiment；

Figure 17 is that tachymeter surveys single timing startup interface figure in the utility model embodiment；

Figure 18 is that tachymeter surveys 16 high speed timing startup interface figures in the utility model embodiment；

Wherein：1st, compressed air gun 2, trip rod 3, source of parallel light 4, incident bar 5, test specimen 6, transmission bar 7, absorbing rod 8th, damper 9, strain ga(u)ge.

Embodiment

With reference to the accompanying drawing in the utility model embodiment, the technical scheme in the embodiment of the utility model is carried out clear Chu, it is fully described by, it is clear that described embodiment is only part of the embodiment of the present utility model, rather than whole Embodiment.Based on the embodiment in the utility model, those of ordinary skill in the art are not under the premise of creative work is made The every other embodiment obtained, belong to the scope of the utility model protection.

Many details are elaborated in the following description in order to fully understand the utility model, but this practicality is new Type can also be different from other manner described here using other to be implemented, and those skilled in the art can be without prejudice to this reality With doing similar popularization in the case of new intension, therefore the utility model is not limited by following public specific embodiment.

Overall, as shown in Fig. 2 the utility model embodiment discloses a kind of intelligence for Hopkinson pressure bar experiment Tachymeter, including 5V power modules, Laser emission pipe power supply circuit, two LASER Discharge Tubes, startup photoelectric receiving tube, stopping light Electric reception pipe, pulse shaper, logical circuit of counter circuit, microcontroller, key circuit, display circuit and interface module.It is described The output end of power module is divided into two-way, and the first via is connected with the power input of the Laser emission pipe power supply circuit, and second Road is connected with the power input of the module outside LASER Discharge Tube, for providing working power for it；The LASER Discharge Tube The power input of power circuit is connected with the power input of the LASER Discharge Tube, for being provided for the LASER Discharge Tube Working power；One LASER Discharge Tube is corresponding with starting photoelectric receiving tube, and another LASER Discharge Tube is with stopping opto-electronic receiver Manage corresponding；The photoelectric receiving tube is used for the laser signal for receiving LASER Discharge Tube transmitting；The signal of the photoelectric receiving tube Input is connected with the signal input part of the pulse shaper, the signal output part of the pulse shaper and the meter The input connection of number logic circuit；Crystal oscillator provides work clock for the logical circuit of counter circuit；The key circuit It is connected with the signal input part of the logical circuit of counter circuit, for inputting control command；The logical circuit of counter circuit and microcontroller It is bi-directionally connected between device；The display circuit is connected with the signal output part of the microcontroller, for showing that microcontroller is defeated The data gone out；The interface module is bi-directionally connected with the microcontroller, for by the tachymeter and data acquisition process system System connects together, and carries out the interaction of data.

The tachymeter is one and is uniformly coordinated the embedded test system that is operated of control by microcontroller, not only may be used To realize testing and control, result display function, and it can realize that data storage, spacing are set, far-end operation, test data pass The function such as defeated, substantially increase the automaticity of experiment.

The external diameter of LASER Discharge Tube is 6mm, wavelength 650nm, power 5mW.In actual applications, if LASER Discharge Tube 5V power supplys are directly connected to, the electric current that LASER Discharge Tube can be caused to flow through is excessive, and aging speed is accelerated, the brightness of laser beam launched Reduce quickly, cause receiving circuit to be properly received optical signal, spy devises the Laser emission pipe power supply circuit shown in Fig. 3. The Laser emission pipe power supply circuit includes diode D1-D2 and resistance R, the diode D1 positive pole meet+5V power supplys, institute The negative pole for stating diode D1 is connected with the positive pole of the diode D2, the negative pole of the diode D2 through the resistance R with it is described The power input connection of LASER Discharge Tube.The 1N4148 diode pair 5V power supplys that the circuit employs 2 series connection are depressured, Then to connect in circuit a 1/4W 100 Ohmic resistances so that the electric current for flowing through LASER Discharge Tube is limited in 10~ 12mA, that is, the requirement of the brightness of laser beam is met, and the cumulative operation time of LASER Discharge Tube is extended.

Pulse shaper includes two structure identical shaping pulse modules, as shown in figure 4, resistance R1 and resistance R2 Node be the shaping pulse module signal input part, a signal input part of the shaping pulse module with it is therein The colelctor electrode connection of one photoelectric receiving tube, the grounded emitter of the photoelectric receiving tube, resistance R1 another termination+5V electricity Source, resistance R2 other end ground connection, the resistance R1 are connected with resistance R2 node with triode Q1 base stage, the triode Q1 colelctor electrode connects+5V power supplys, and the emitter stage of the triode Q1 is divided into two-way, and the first via is grounded through resistance R3, the second tunnel with Triode Q2 base stage connection, a resistance R4 termination+5V power supplys, the resistance R4 other end are divided into two-way, the first via and three poles Pipe Q3 base stage connection, the second tunnel are connected with triode Q2 colelctor electrode, and triode Q2 emitter stage is grounded through resistance R5；It is described Triode Q3 colelctor electrode is divided into two-way, and the first via is connected with+5V power supplys, and the second tunnel is grounded through electric capacity C10；Triode Q3 hair Emitter-base bandgap grading is divided into two-way, is grounded all the way with the signal output part of the shaping pulse module, another way through resistance R6.

Start, stopping photoelectric receiving tube is phototriode, model PT334-6C, diameter 5mm, operating spectral range is It is its sensitivity peaks when 400~1100nm, 940nm.Pulse shaper is mainly used in peak value caused by photoelectric receiving tube About 2.4V photoelectric pulse signal is shaped as Transistor-Transistor Logic level signal, is changed into starting " startup " of counter works and " stops Only " signal.Its operation principle is, when phototriode Q0 is irradiated by laser beam, Q0 conductings, now Q1 b poles level is 0.4V, Q1 end, and Q2 b extremely 0V, Q2 are also at off-state, and then Q3 b poles are in high level, Q3 saturation conductions, Q3 Emitter stage output be about 4.2V high level；After laser beam, which is knocked pole spacing, lives, Q0 cut-offs, Q1 b poles level is changed into 2.4V, now Q1 turn on, Q2 is also at conducting state, and Q2 c poles level is about 0.4V, and Q3 is in off-state, and Q3 emitter stage is defeated Go out 0V low level.In this circuit arrangement, Q1 and Q2 serves the effect of comparator, and threshold value is about 1.2V, and Q3 serves emitter-base bandgap grading The effect of follower.For the pulse shaper of the tester compared with Fig. 1 experimental provision, the circuit is mainly characterized by structure Simply, amplifier circuit has been given up, compared with very high speed integrated circuit comparator, bandwidth can reach 150MHz, but cost will Cheap is more.

As shown in figure 5, the logical circuit of counter circuit, which includes starting, stops logic circuit, 20 up counters, 8 additions Counter, stop counting interrupt logic circuit, start halted state latch, counter Q19-Q16 latch, counter Q15-Q8 latch, counter Q7-Q0 latch, self-test counter Q7-Q0 latch, key-press status latch, output selection Logic circuit and output multi-channel selector；The output for starting the input and the pulse shaper that stop logic circuit End connection, the enabling signal output end for starting stopping logic circuit being divided into two-way, the first via and 20 plus coujnts The input connection of device, the second tunnel are connected with the input of the startup halted state latch；Described start stops logic electricity The stop signal output end on road is divided into three tunnels, and the first via is connected with the input of 20 up counters, and the second tunnel is stopped with startup Only the input connection of status latch, the 3rd tunnel are connected with stopping the input of counting interrupt logic circuit, described to stop meter The output end of number interrupt logic circuit is interrupt signal output end；It is described start halted state latch output end with it is described defeated Go out the input connection of MUX；Clock signal respectively with 20 up counters and 8 plus coujnts The input connection of device, input of the reset signal respectively with 20 up counters and 8 up counters are connected, Self-test signal is connected with the input of 8 up counters；Three output ends of 20 up counters pass through respectively The counter Q19-Q16 latch, counter Q15-Q8 latch, counter Q7-Q0 latch and the output multi-channel select Select three signal input parts connection of device；The output end of 8 up counters is through the self-test counter Q7-Q0 latch and institute The input connection of output multi-channel selector is stated, the output end of key circuit and the input of the key-press status latch connect Connect, the output end of the key-press status latch is connected with the input of the output multi-channel selector, the output of microcontroller End selects logic circuit to be connected with the input of the output multi-channel selector through the output, the output multi-channel selector Output end is connected with the signal input part of the microcontroller.

The programmable logic chip programming realization that logical circuit of counter circuit is about 30mm × 30mm × 2mm by appearance and size, type Number it is MAX7128S, counting clock signal reaches as high as 150MHz；MAX7128S programmings are based on QuartusII9.0 softwares and realized, Programming language is VHDL, and programming file is downloaded using jtag interface ISP, and function upgrading is very convenient；Designed logical circuit of counter If circuit structure is as shown in figure 5, form the logical circuit of counter circuit of identical functions using 74 serial TTL integrated circuits, not only electric Line structure is once it is determined that can not just change, and PCB sizes are very big, and connection line length is longer, and counting clock signal highest can not More than 20MHz.

The input of logical circuit of counter circuit has the startup that pulse shaper exports, stop signal, and 10MHz crystal oscillators are defeated The clock signal entered, the clearing of microcontroller input, self-test, output gate logic control signal (P2.4~P2.0), 3 are pressed Key signals, output, which has, stops counting interrupt signal (INT0), P0.7~P0.0 data bus signals.

Logical circuit of counter circuit mainly includes 6 parts：Basic counter, it is main to include starting stopping logic circuit, 20 additions Counter, wherein starting the flip-flop circuit (Fig. 6) for stopping that logic circuit is a not reproducible triggering, it can will start, stop Pulse signal is changed into Start, Stop logic state signal, and stop pulse triggering is controlled by Start logical circuit of counter state letter Number, it is therefore prevented that 20 up counter miscounts and repeat count；8 self-test up counters, self-test signal are its enabled letter Number, when self-test signal is effective, then can to 10MHz clock signal since 0 continuous counter, until 0XFF stops, for surveying Examine 10MHz clock signals whether normal before examination；Stop counting interrupt circuit, be mainly used in when Stop signals are effective, produce INT0 signal outputs feed them into interrupt routine, prepare to read the count value of basic counter to microcontroller；Output gating is patrolled Collect circuit and MUX is used for solving timesharing reading problem of the microcontroller to logical circuit of counter circuit output latch； Start, Stop status latch are mainly used in microcontroller and read Start, Stop state, judge whether counting process has Effect, and non-counter failure；Key-press status latch is used for " pressing " or the "off" state for storing 3 buttons, for micro-control Device processed scans keyboard, solves the problems, such as its I/O port deficiency.

Further, as shown in fig. 6, the logical circuit of counter circuit just triggers double D trigger using 7474 band set-resets Form to start and stop logic circuit.

Microcontroller, display and the interface section of tachymeter are mainly made up of STC89C52RC, MAX3232, LCD1602 (as shown in Figure 7).Microcontroller STC89C52RC uses 11.0592MHz crystal oscillators, to ensure RS232 traffic rates 9600bps standards Really, RS232 data high reliability transports are ensured；MAX3232 completes the Transistor-Transistor Logic level of serial communication to RS232 level conversions, so It is connected afterwards with the RS232 interface of host computer；LCD1602 is the conventional character liquid crystal display of 2 row 16, carries display chip, Data-interface line D0~D7 is connected with STC89C52RC P1.0~P1.7 mouths, LCD_RS, LCD_RW, LCD_EP points of control line P3.3, P3.5, P4.0 are not controlled by it.

Tachymeter working software is developed based on Keil C51, and the main block diagram of its program is as shown in Figure 8.It can be seen from main block diagram, After the completion of the initialization of program startup optimization, self-test can be carried out to basic counter and self-test counter, if self-test is not by showing Show mistake；If self-test according to the key of return by into key scan program, performing and testing the speed program or set survey Speed returns to main program apart from subprogram after having performed；If button is not pressed, judge whether to interrupt there occurs serial, i.e., Whether host computer have sent order；In the event of serial interruption, then corresponding sub- journey is performed according to the command code of host computer Sequence, such as it is single or multiple test the speed, test the speed distance setting, test the speed distance upload, electronic tag upload, main journey is returned after being finished Sequence, if software reset, system performs since program origin automatically.

Tachymeter electronic tag is stored in customizing messages in STC89C52RC EEPROM regions, contains instrument class The information such as type, software version, intellectual property, STC89C52RC can be read and be uploaded to host computer；In repeatedly testing the speed, Program can be every time by surveyed data automatic temporary storage in microprocessor STC89C52RC RAM, will wherein after the completion of test Data are uploaded or are stored in STC89C52RC EEROM after reading again, to be lost after power down preventing.

The subroutine program block diagram that tests the speed is as shown in Figure 9.During testing the speed, first by basic counter, start stopping logic Circuit is reset, and is then opened external interrupt INT0, after master counter count terminates, INT0 interrupt responses, is then read in first Start, Stop latch state value, if both at " 1 ", illustrate that this test is effective, otherwise show test errors；Such as Fruit test is effective, then reads in the count value of basic counter, and calculates depression bar speed according to the setting distance that tests the speed, then analytic accounting number Device count value is sent to host computer, and shows the result that tests the speed in LCD display.

Upper computer software utilizes Virtual Instrument Development software LabWindows/CVI using Windows XP as operating platform Exploitation forms, and is mainly controlled using RS232 interface function pair tachymeter, can complete electronic tag reading, single is surveyed Speed starts, measuring distance is set, measuring distance is read, startup of repeatedly testing the speed, and display and preliminary point can be carried out to the result that tests the speed Analysis.

The tachymeter main feature is as follows：

LCD display interfaces are succinct, and operation indicating is clear and definite, can show testing time value and velocity amplitude simultaneously；It can set manually Test the speed segment distance, and setting scope is 1~999mm, resolution ratio 1mm, gives tacit consent to 50mm；Time test scope be 0.1~ 99999.9us (0.1s), resolution ratio are ± 0.1us, and velocity resolution is ± 0.01m/s；, can basis with serial communication interface User's request design PC control software control test process；Power supply is AC220V, operating temperature -10~40 DEG C.

The tachymeter front panel has power switch, a SR, 3 Cao Zuoanjians (" it is determined that ", "+", "-"), LCD Display；Back panel has a 220V power outlets, serial communication socket, and 2 LASER Discharge Tube power supplys export BNC sockets, 1 Enabling signal BNC socket, 1 stop signal BNC socket.

Test process is specific as follows：

One, preparations

(1) power line is utilized by AC220V plant-grid connection instruments in instrument rear board；

(2) by BNC cables, 2 Laser Power Devices BNC sockets of rear board are led into Laser emission component；(3) lead to BNC cables are crossed, " startup " corresponding to laser pick-off component and "signal for " stop " are introduced into tachymeter from rear board BNC socket.

2nd, operate with method

1st, shown by the power knob on lower panel, LCD display

“Welcome”

“Time Test V1.0”

If startup self-detection mistake, shows

“Error01”

“Reset or Check！”

Instrument should be now restarted, if occurring same mistake again, illustrates that instrument is faulty, inspection please be send back to Repair.

2nd, after self-test success, main menu (as shown in Figure 10) is shown.

“1.Test time”

“2.Set Distance”

Now cursor can be parked on menu 1, if selection menu 1, press " it is determined that " button, then instrument beginning In test mode, as shown in Figure 10.

After being completed, interface can show test result, such as：

" t=70.5us "

" v=141.68m/s "

3rd, if necessary to selection menu 2, then the "+" button is pressed, cursor moves down automatically, and presses confirming button again, instrument Perform apart from setting program, display Figure 11 interfaces.

The distance range that instrument can be set is 1~999mm.As shown in figure 12, present cursor, can be continuous in hundreds "+" or "-" key adjustment numeral are pressed, until untill satisfied, press " it is determined that " after key, cursor moves to tens, with hundreds tune Adjusting method is identical.After units has been adjusted, press " it is determined that " key, the distance value set by user can be prompted on interface, so The main interface shown in Figure 10 is returned afterwards.

3rd, the host computer remote control application method based on RS232 serial ports

1. after being connected between host computer and tachymeter with null modem cable, start host computer procedure, occur such as Figure 13 institutes Show interface.

2. clicking on " reading electronic tag " button, the electronic tag of tachymeter storage inside can be read, and controlled accordingly Shown in part, as shown in figure 14.After tachymeter end of transmission, LCD display shows " E-Label->PC ", " RS232TX End！”.Using the electronic tag of reading, operating personnel can immediately determine that the lot number of tachymeter, software version number, software download The information such as time, be highly convenient for the maintenance of tachymeter.

3. click on " MCU->PC " buttons, the current set distance value that tests the speed of tachymeter can be read, such as Figure 15 institutes Show, the distance that tests the speed of slave computer setting is 40mm.After end of transmission, the LCD display of tachymeter is shown：" Distance-> PC”,“RS232TX End！”.

4. click on " PC->MCU " buttons, the current set survey of tachymeter will can be down passed apart from setting value on the right side of it Fast distance value is read, as shown in figure 16.After end of transmission, the LCD display of tachymeter is shown：" Distance->MCU”,“d =50mm ".

5. clicking on " single timing startup " button, start tachymeter work, after the completion of testing the speed, host computer receives tachymeter The timing result sent, and shown in corresponding control, as shown in figure 17.After end of transmission, the LCD of tachymeter is shown Device is shown：“RS232TX End！", " Count num=1 ".

6. clicking on " 16 high speed timing startup " button, start tachymeter work, after the completion of testing the speed, host computer receives survey Fast instrument sends 16 timing results, and is shown in corresponding control, as shown in figure 18.After end of transmission, tachymeter LCD display is shown：“High_Vel Count”“RS232TX End！”.From high speed timing startup interface, this is 16 times Average value, variance, maximum and the minimum value of timing.

Claims (10)

1. A kind of 1. INTELLIGENT TACHOMETER for Hopkinson pressure bar experiment, it is characterised in that：Including 5V power modules, Laser emission Pipe power supply circuit, two LASER Discharge Tubes, start photoelectric receiving tube, stop photoelectric receiving tube, pulse shaper, logical circuit of counter Circuit, microcontroller, key circuit, display circuit and interface module, the output end of the power module are divided into two-way, the first via It is connected with the power input of the Laser emission pipe power supply circuit, the second tunnel and the power supply of the module outside LASER Discharge Tube are defeated Enter end connection, for providing working power for it；The power input of the Laser emission pipe power supply circuit is sent out with the laser The power input connection of pipe is penetrated, for providing working power for the LASER Discharge Tube；One LASER Discharge Tube is with starting light Electric reception pipe is corresponding, and another LASER Discharge Tube is corresponding with stopping photoelectric receiving tube；The photoelectric receiving tube is used to receive The laser signal of LASER Discharge Tube transmitting；The signal of the signal input part of the photoelectric receiving tube and the pulse shaper is defeated Enter end connection, the signal output part of the pulse shaper is connected with the input of the logical circuit of counter circuit；Crystal oscillation Device provides work clock for the logical circuit of counter circuit；The signal input part of the key circuit and the logical circuit of counter circuit connects Connect, for inputting control command；It is bi-directionally connected between the logical circuit of counter circuit and microcontroller；The display circuit with it is described The signal output part connection of microcontroller, for showing the data of microcontroller output；The interface module and the microcontroller Device is bi-directionally connected, and for the tachymeter to be connected together with data acquisition processing system, carries out the interaction of data.
2. 2. it is used for the INTELLIGENT TACHOMETER of Hopkinson pressure bar experiment as claimed in claim 1, it is characterised in that：The laser hair Penetrate positive pole of the pipe power supply circuit including diode D1-D2 and resistance R, the diode D1 and connect+5V power supplys, the diode D1's Negative pole is connected with the positive pole of the diode D2, and the negative pole of the diode D2 is through the resistance R and the LASER Discharge Tube Power input connects.
3. 3. it is used for the INTELLIGENT TACHOMETER of Hopkinson pressure bar experiment as claimed in claim 1, it is characterised in that：Shaping pulse electricity Road includes two structure identical shaping pulse modules, and resistance R1 and resistance R2 node is the signal of the shaping pulse module Input, a signal input part of the shaping pulse module connect with the colelctor electrode of one of those photoelectric receiving tube Connect, the grounded emitter of the photoelectric receiving tube, resistance R1 another termination+5V power supplys, resistance R2 other end ground connection, the electricity Resistance R1 is connected with resistance R2 node with triode Q1 base stage, and the colelctor electrode of the triode Q1 connects+5V power supplys, three pole Pipe Q1 emitter stage is divided into two-way, and the first via is grounded through resistance R3, and the second tunnel is connected with triode Q2 base stage, and the one of resistance R4 Termination+5V power supplys, the resistance R4 other end are divided into two-way, and the first via is connected with triode Q3 base stage, the second tunnel and triode Q2 colelctor electrode connection, triode Q2 emitter stage are grounded through resistance R5；The colelctor electrode of the triode Q3 is divided into two-way, and first Road is connected with+5V power supplys, and the second tunnel is grounded through electric capacity C10；Triode Q3 emitter stage is divided into two-way, whole with the pulse all the way The signal output part of shape module, another way are grounded through resistance R6.
4. 4. it is used for the INTELLIGENT TACHOMETER of Hopkinson pressure bar experiment as claimed in claim 1, it is characterised in that：The counting is patrolled Volume circuit include starting stop logic circuit, 20 up counters, 8 up counters, stop counting interrupt logic circuit, Start halted state latch, counter Q19-Q16 latch, counter Q15-Q8 latch, counter Q7-Q0 latch, Self-test counter Q7-Q0 latch, key-press status latch, output selection logic circuit and output multi-channel selector；It is described to open The dynamic input for stopping logic circuit being connected with the output end of the pulse shaper, and described start stops opening for logic circuit Dynamic signal output part is divided into two-way, and the first via is connected with the input of 20 up counters, the second tunnel and the startup The input connection of halted state latch；Described start stops the stop signal output end of logic circuit and is divided into three tunnels, and first Road is connected with the input of 20 up counters, and the second tunnel is connected with starting the input of halted state latch, the 3rd tunnel It is connected with the input for stopping counting interrupt logic circuit, the output end for stopping counting interrupt logic circuit is interrupt signal Output end；The output end for starting halted state latch is connected with an input of the output multi-channel selector；When Input of the clock signal respectively with 20 up counters and 8 up counters is connected, reset signal respectively with institute The input connection of 20 up counters and 8 up counters is stated, self-test signal is defeated with 8 up counters Enter end connection；Three output ends of 20 up counters are respectively through the counter Q19-Q16 latch, counter Q15-Q8 latch, counter Q7-Q0 latch are connected with three signal input parts of the output multi-channel selector；8 add The output end of method counter is connected through the self-test counter Q7-Q0 latch with the input of the output multi-channel selector, The output end of key circuit is connected with the input of the key-press status latch, the output end of the key-press status latch with The input connection of the output multi-channel selector, the output end of microcontroller through the output select logic circuit with it is described defeated Go out the input connection of MUX, the output end of the output multi-channel selector and the signal input part of the microcontroller Connection.
5. 5. it is used for the INTELLIGENT TACHOMETER of Hopkinson pressure bar experiment as claimed in claim 4, it is characterised in that：The counting is patrolled Collect circuit and just triggering double D trigger using 7474 band set-resets and forming to start and stop logic circuit.
6. 6. it is used for the INTELLIGENT TACHOMETER of Hopkinson pressure bar experiment as claimed in claim 1, it is characterised in that：The microcontroller Device uses STC89C52RC type single-chip microcomputers.
7. 7. it is used for the INTELLIGENT TACHOMETER of Hopkinson pressure bar experiment as claimed in claim 1, it is characterised in that：The interface mould Block is serial communication interface module.
8. 8. it is used for the INTELLIGENT TACHOMETER of Hopkinson pressure bar experiment as claimed in claim 7, it is characterised in that：It is described serial logical Letter interface module is RS232 interface module.
9. 9. it is used for the INTELLIGENT TACHOMETER of Hopkinson pressure bar experiment as claimed in claim 8, it is characterised in that：The RS232 Interface module uses MAX3232 cake cores.
10. 10. it is used for the INTELLIGENT TACHOMETER of Hopkinson pressure bar experiment as claimed in claim 1, it is characterised in that：The display Circuit uses LCD1602 type LCD MODULEs.