String vibration type sensor with digital memory
Technical field: the present invention relates to sensor field, relate in particular to the technological improvement and the innovation of vibrating string type sensor.
Background technology: vibrating string type sensor, be that the natural frequency of vibration according to the fixing string wire in two ends is directly proportional with tension force, and the tension force of the string wire relation that be deformed into direct ratio suffered and a kind of sensor made from it, it is widely used in the physical quantity such as strain, stress, pressure, displacement of inspected object, because its material guarantees and direct output frequency signal, therefore there is not zero point drift, long-time stability are good, thereby are used widely in fields such as water conservancy and hydropower, railway, traffic, buildings; But used vibrating string type sensor has following shortcoming: 1. sensor output is the practical frequency value, and also must convert according to calibration curve just to draw the measurand of object, and test speed is slow, and is high to tester's technical merit requirement; 2. the practical frequency value of sensor output belongs to faint AC signal without data processing and modulation, can not make long-distance transmissions; 3. when being embedded in a large number, sensor does in the engineering structure during the long-term quality monitoring, stained or the interruption of sensor transmissions cable easily takes place, cause sensor number and calibrating parameters to lose, so that generation obtains the invalid data situation that frequency values also can't be calculated the respective physical amount.
Summary of the invention: technical matters to be solved by this invention, be to provide a kind of can be under transmission cable breakdown situation, also can directly record required physical quantity, and can make the string vibration type sensor with digital memory of long-distance transmissions.
For this reason, technical scheme of the present invention is: a kind of string vibration type sensor with digital memory, has a seal casinghousing between its two ends seat, being packaged with one in the housing is the tensioning string wire of fulcrum with the two ends seat, and a permanent magnet, an inductive coil vertically are encapsulated in the relative both sides of string wire with string wire respectively; Wherein, inductive coil receives the test pulse of input, output magnetic exciting force, string wire is subjected to the magnetic exciting force to excite the generation single vibration, the string wire single vibration cutting permanent magnet magnetic line of force, generate the a-c cycle signal in the inductive coil again and export to treatment circuit, it is characterized in that: described treatment circuit is by AC amplifier, singlechip chip, the serial storage chip, serial interface chip connects composition in regular turn, wherein: AC amplifier is connected with the output terminal of inductive coil with input end, receive the a-c cycle signal of self-induction coil, the frequency signal that output is amplified; Singlechip chip is connected with the output terminal of AC amplifier with the I/O interface, receives the frequency signal that amplifies, output numerical signal/instruction; The serial storage chip is connected with the access hole of singlechip chip with access port, accepts the numerical signal/instruction from singlechip chip, stores or access numerical signal; Serial interface chip is connected with the serial line interface of singlechip chip with the control mouth, receives the numerical signal/instruction from singlechip chip, sends serial signal outside or accepts external serial command by the transmitting-receiving mouth.
Described treatment circuit comprises AC amplifier, singlechip chip, serial storage chip, serial interface chip, with the string wire of permanent magnet, inductive coil and tensioning together, all be packaged in the seal casinghousing between the seat of two ends.
Described singlechip chip is a MCS-51 series monolithic chip.
Described serial storage chip is that electricity can be write ROM (read-only memory), and described serial interface chip is the RS232 type.
Also lead to the external cable that comprises two signal wires and two power leads on the seal casinghousing of described string vibration type sensor with digital memory.
Owing to adopted above-mentioned technological improvement, the present invention compares with existing vibrating string type sensor following advantage: 1. the numerical value through single-chip microcomputer etc. converts, handles, sensor can directly be exported measurand, sensor number, calibrating parameters and measurement environment parameter etc., the trouble of having removed artificial calculating from of showing directly perceived; 2. number of sensor, calibrating parameters etc. permanently are stored in the memory chip of sensor, and can when each the measurement, preserve automatically and survey parameter for 800 times as: Measuring Time, measuring point temperature, zero point parameter, temperature modified value etc., therefore, even the transmission cable breakdown of sensor is as long as reclose and can access original and historical test data and recover new test from sensor; 3. output is digital signal but not faint induction AC signal, so can realize long-distance transmissions.Therefore the present invention has significant advance in this area.
Description of drawings: followingly in conjunction with the accompanying drawings the present invention is made an explanation again.
Fig. 1 is the structural principle block diagram of the embodiment of the invention.
Fig. 2 is the circuit interconnect pattern of the embodiment of the invention.
Fig. 3 is the schematic appearance of the embodiment of the invention.
Embodiment: as shown in Figure 1: a kind of string vibration type sensor with digital memory, has a seal casinghousing between its two ends seat 1-1,1-2, being packaged with one in the housing is that 2, one permanent magnets of tensioning string wire 3 of fulcrum, an inductive coil 4 vertically are encapsulated in string wire 2 relative both sides with string wire 2 respectively with two ends seat 1-1,1-2; Wherein, inductive coil 4 receives the test pulse of input, output magnetic exciting force, string wire 2 is subjected to the magnetic exciting force to excite the generation single vibration, string wire 2 single vibrations cutting permanent magnet 3 magnetic lines of force, generate the a-c cycle signal in the inductive coil 4 again and export to treatment circuit, it is characterized in that: described treatment circuit is connected in regular turn by AC amplifier 5, singlechip chip 6, serial storage chip 7, serial interface chip 8 and forms
As shown in Figure 2: the string vibration type sensor with digital memory of the embodiment of the invention, its circuit is: inductive coil 4 is converted into the magnetic exciting force to excite string wire 2 generation single vibrations with the test pulse of input, then string wire 2 unidirectional excitings being cut permanent magnet 3 magnetic lines of force responds to the a-c cycle signal of generation again and exports to treatment circuit, it is characterized in that: described treatment circuit is by AC amplifier 5, singlechip chip 6, serial storage chip 7, serial interface chip 8 connects composition in regular turn, wherein: AC amplifier 5 with input end (, +) be connected with the output terminal of inductive coil 4, the a-c cycle signal that comes self-induction coil 4 is amplified the frequency signal that output is amplified; MCS-51 type singlechip chip 6 is connected with the output terminal of I/O interface with AC amplifier 5, and the frequency signal that amplifies is carried out the logical and numerical operation, output numerical signal/instruction; The 24C64 electricity can be write read-only serial storage 7 and be connected with the access hole (SDA, SCL pin) of MCS-51 type singlechip chip 6 with access port, and the numerical signal/instruction according to from singlechip chip 6 stores or access numerical signal; RS232 type serial interface chip 8 is connected with the serial line interface (RXD, TXD pin) of MCS-51 singlechip chip 6 with the control mouth, according to numerical signal/instruction from singlechip chip 6, implement the conversion between numerical signal and serial signal, and send serial signal outside or accept external serial command by its transmitting-receiving mouthful S1, a S2.Described string vibration type sensor with digital memory also leads to two signal wire S1, S2 and two power lead P1, P2; Wherein P1 is connected with ground wire GND, and P2 is connected with the power lead Vcc of each element circuit.
Shown in Fig. 1,3: the string vibration type sensor with digital memory of the embodiment of the invention, have a seal casinghousing between its two ends seat 1-1,1-2 and comprise string pipe 9-1 and casing 9-2, be packaged with in the string pipe 9-1: a tensioning string wire 2 that is fulcrum with two ends seat 1-1,1-2 is packaged with in the casing 9-2: permanent magnet 3, an inductive coil 4 and described treatment circuit comprise AC amplifier 5, singlechip chip 6, serial storage chip 7, serial interface chip 8; Also lead to the external cable C that comprises two signal wire S1, S2 and two power lead P1, P2 on the casing 9-2.
Now further specify its practical principle: in the practicality in conjunction with above-mentioned all figure, with two ends seat 1-1,1-2 ties up respectively or is adhesively fixed on 2 that fix on testee along deformation direction, the distortion of object passes to the string wire 2 between the seat of two ends, when measuring current is passed through two power lead P1, P2 and inductive coil 4 excite string wire 2 to make the single vibration cutting magnetic line, the output of a-c cycle signal is arranged on the inductive coil 4, through amplifying, numerical value is handled, the raw data of test is at every turn exported by serial interface chip 8, show measurand, to test gained data and environment simultaneously, sensor characteristic parameter etc. is stored in singlechip chip 6 or the serial storage 7, in order to transferring inquiry later at any time, even signal wire S1, S2 and power lead P1, the unexpected breakdown of P2, as long as again with its connection, primary characteristic parameter and sensor number etc. be can access, various computings and new test carried out; And the test physical quantity that quantizes is not subjected to the restriction of long distance transmission, and is convenient and swift.