CN2519251Y

CN2519251Y - Hand held vibration measuring apparatus

Info

Publication number: CN2519251Y
Application number: CN 02212486
Authority: CN
Inventors: 霍孟友; 路长厚
Original assignee: Shandong University
Current assignee: Shandong University
Priority date: 2002-01-28
Filing date: 2002-01-28
Publication date: 2002-10-30
Anticipated expiration: 2012-01-28

Abstract

The utility model which relates to a hand held type vibration measuring instrument that can realize the measurement of the vibration frequency and amplitude of objects under the stabilized vibration state consists of a single chip machine, an acceleration sensor, a preamplifier, a middle amplifier, a shaping circuit, a sample keeping circuit, an A/D conversion circuit, a keyboard circuit, a display circuit and a battery power supply circuit; the utility model has the advantages of small structure, low energy consumption and low cost; the single chip machine regulates the amplifier plus according to the over range or the lack range information output by the A/D conversion circuit, of which leads the measurement to have a higher sensitivity, and the utility model is suitable to the measurement of the vibration frequency and amplitude of objects in a wider amplitude range and a wider frequency range under the stabilized vibration state.

Description

The hand-held vibration measuring set

1, technical field

The utility model belongs to fields of measurement, particularly relates to a kind of hand-held vibration measuring set of realizing that object vibration frequency and vibration amplitude are measured under the stable oscillation state.

2, background technology

Vibration frequency and vibration amplitude are two important parameters describing the vibrating object vibrational state.Present existing hand-held vibration measuring set mainly is divided into two classes: a class is the micro-vibration measuring instrument of similar penholder, and another kind of is that volume is big, the vibration measuring set of function complexity, but all there is certain technical limitation in both.The former measurement range is limited, if any the amplitude measurement maximum of micro-vibration measuring instrument can only reach 1.999mm, be not suitable for the measurement of the big object vibration parameter of vibration amplitude; And latter's function complexity (can also carry out other complicated algorithm analyses measuring amplitude and frequency values), overall power except finishing big (utilizing battery not power for a long time), cost are higher, not too be fit to more open-air only simple special occasions (as the measurement of street roller duty) uses of measuring amplitudes and frequency values of needs.

3, summary of the invention

The purpose of this utility model is to overcome the technical limitation of existing vibration measuring set, provide a kind of and adopt powered battery, can realize the hand-held vibration measuring set that object under the stable oscillation state is measured than the vibration amplitude and the vibration frequency of wide amplitude range and wider frequency range, as a kind of between micro-vibration measuring instrument and function complex vibration measuring instrument, that structure is small and exquisite, the novel vibrating measuring instrument that can be satisfied with some special occasions use.

The utility model is realized in the following manner:

The hand-held vibration measuring set, it comprises single-chip microcomputer, acceleration transducer, prime amplifier, intermediate amplifier, shaping circuit, sampling hold circuit, A/D change-over circuit, keyboard circuit, display circuit and battery feed circuit; Acceleration transducer is imported charge signal by shielded cable to prime amplifier, the output of prime amplifier is as the input of intermediate amplifier, the output of intermediate amplifier is as the input of shaping circuit and sampling hold circuit, the square-wave pulse signal that shaping circuit provides vibration frequency to measure for single-chip microcomputer, the output of sampling hold circuit is as the input of A/D change-over circuit, the digital quantity signal that the A/D change-over circuit provides vibration amplitude to measure for single-chip microcomputer, keyboard circuit is used for the operation of people to single-chip microcomputer, display circuit shows measurement result and status information, and battery feed circuit provides operating voltage for system; Feature of the present utility model is: the sampling hold circuit sampling keeps the peak signal of input signal, the A/D change-over circuit adopts the A/D converter that has overrange and owe the range measuring ability, intermediate amplifier adopts digital regulation resistance and by single-chip microcomputer gain is regulated, keyboard circuit adopts the triple bond bit keyboard, and being respectively applied for the measuring process startup, stopping with displaying contents is the selection control of frequency values or amplitude; Display circuit adopts 4 LCD, the flash for prompting information when being used to show vibration frequency value, vibration amplitude or battery under-voltage condition.

Because single-chip microcomputer of the present utility model is according to the overrange of A/D change-over circuit and owe the gain of range information pair amplifier and automatically adjust, as long as therefore select for use appropriate acceleration sensor, the utility model promptly to have higher measurement sensitivity; In addition, the device that the utility model is selected for use mostly is low energy-consumption electronic device, and single-chip microcomputer moves with battery saving mode, can utilize powered battery to carry out long surveying work.

4, description of drawings:

Fig. 1 is a block diagram of the present utility model.

1 is keyboard circuit among the figure, and 2 is display circuit, and 3 is prime amplifier, and 4 is intermediate amplifier, and 5 is sampling hold circuit, and 6 is shaping circuit, and 7 is acceleration transducer, and 8 is battery feed circuit, and 9 is the A/D change-over circuit, and 10 is single-chip microcomputer.5, specific implementation method

Below in conjunction with accompanying drawing the utility model is elaborated:

The utility model comprises that model is single-chip microcomputer 10, strain gauge acceleration transducer 7, prime amplifier 3, intermediate amplifier 4, shaping circuit 6, sampling hold circuit 5, A/D change-over circuit 9, keyboard circuit 1, display circuit 2 and the battery feed circuit 8 of AT89C51.Prime amplifier 3 is finished impedance conversion and is amplified with preliminary signal, and the quantity of electric charge signal of acceleration transducer 7 outputs is converted into voltage signal; Intermediate amplifier 4 further amplifies the output signal of prime amplifier 3, and it has adopted digital regulation resistance to regulate gain, and digital regulation resistance is controlled by single-chip microcomputer 10; Prime amplifier 3 and intermediate amplifier 4 have all adopted the MOS operational amplifier LF444 of low-power consumption, high input impedance; Shaping circuit 6 is converted into pulse square wave signal to the signal that changes with sinusoidal wave form of intermediate amplifier 4 outputs, delivers to the timer input end of single-chip microcomputer 10, utilizes the method realization vibration frequency value of measuring the recurrence interval to measure; Sampling hold circuit 5 constitutes the peak signal sampling hold circuit by operational amplifier, NMOS pipe T and capacitor C, makes the voltage of capacitor C remain the crest voltage value of input sine wave signal; A/D change-over circuit 9 is converted into digital quantity to the signal that sampling hold circuit 5 samplings keep, and A/D converter spare has been selected high precision, the low energy-consumption electronic device ICL7135 that has overrange and owe the range measuring ability for use; Keyboard circuit 1 is the triple bond bit keyboard, and a key is used for the measuring process start-up control, and a key is used for the time-out control of measuring process, and other has a key to be used for the selection control that displaying contents is vibration amplitude or vibration frequency value; Display circuit 2 is 4 LCD display, flash for prompting information when being used to show vibration frequency value, vibration amplitude or battery under-voltage condition, when showing the vibration amplitude content, the highest one is integer-bit (mixed decimal point), three of backs be decimal place, and during demonstration vibration frequency value, displaying contents is integer-bit entirely, 4 LCD flickers show font " 8 " when battery is under-voltage, and the prompting people change battery; Battery feed circuit 8 the voltage transitions of two batteries be system works need+5V and-the 5V working power, it also has the battery voltage detection function, provides detection signal to single-chip microcomputer 10 when battery is under-voltage.

When measuring beginning, the system initialization routine of single-chip microcomputer 10 is set at a value (regulating the digital regulation resistance in the intermediate amplifier 4) to the gain amplifier of intermediate amplifier 4, starts A/D change-over circuit 9 then and changes; During EOC, single-chip microcomputer 10 at first detects the overrange of A/D change-over circuit 9 and owes range output, if be overrange output, the yield value that intermediate amplifier 4 is described is bigger, single-chip microcomputer 10 outputs are regulated and are reduced yield value, if for owing range output, illustrate that yield value is less, single-chip microcomputer 10 outputs are regulated and are increased yield value; After the gain-adjusted, single-chip microcomputer 10 working routines start A/D change-over circuit 9 once more to be changed, and till not having overrange and owing range information output, at this moment the utility model enters normal surveying work program.During normal the measurement, single-chip microcomputer 10 is when starting A/D change-over circuit 9, and the timer that starts single-chip microcomputer 10 carries out timing to the individual pulse cycle of shaping circuit 6 inputs; The T as a result of individual pulse period measurement being handled can obtain vibration frequency value f=1/T, is D=kA ω and the D as a result (digital quantity corresponding with peak value) of A/D change-over circuit 9 conversions and vibration frequency value f are carried out expression formula ²=k4 π ²Af ²Overall treatment, can obtain vibration amplitude A, k is and the relevant scale-up factor of gain.A and f are carried out smoothing processing respectively, can obtain the vibration amplitude of stable oscillation state object and the stably measured value of vibration frequency.

This shows that the utility model is suitable for the vibration frequency value and the vibration amplitude value of vibrating object under the stable oscillation state and measures.

Claims

1, hand-held vibration measuring set, it comprises single-chip microcomputer [10], acceleration transducer [7], prime amplifier [3], intermediate amplifier [4], shaping circuit [6], sampling hold circuit [5], A/D change-over circuit [9], keyboard circuit [1], display circuit [2] and battery feed circuit [8]; Acceleration transducer [7] is imported charge signal by shielded cable to prime amplifier [3], the output of prime amplifier [3] is as the input of intermediate amplifier [4], the output of intermediate amplifier [4] is as the input of shaping circuit [6] and sampling hold circuit [5], the square-wave pulse signal that shaping circuit [6] provides vibration frequency to measure for single-chip microcomputer [10], the output of sampling hold circuit [5] is as the input of A/D change-over circuit [9], the digital quantity signal that A/D change-over circuit [9] provides vibration amplitude to measure for single-chip microcomputer [10], keyboard circuit [1] is connected to the input circuit of single-chip microcomputer [10], and display circuit [2] is connected to the output circuit of single-chip microcomputer [10]; Feature of the present utility model is: sampling hold circuit [5] sampling keeps the peak signal of input signal, A/D change-over circuit [9] adopts the A/D converter that has overrange and owe the range measuring ability, intermediate amplifier [4] adopts digital regulation resistance and by single-chip microcomputer [10] gain is regulated, keyboard circuit [1] adopts the triple bond bit keyboard, and display circuit [2] adopts 4 LCD.