CN204988462U

CN204988462U - A instrument of weighing for metal material fatigue damage test

Info

Publication number: CN204988462U
Application number: CN201520802565.1U
Authority: CN
Inventors: 侯朝国; 黄斌杰; 杨世锋; 司家勇
Original assignee: Central South University of Forestry and Technology
Current assignee: Central South University of Forestry and Technology
Priority date: 2015-10-16
Filing date: 2015-10-16
Publication date: 2016-01-20
Anticipated expiration: 2025-10-16

Abstract

The utility model discloses an instrument of weighing for metal material fatigue damage test, including weighing sensor, enlarged module, AD converter, digital processing circuit, memory, display and a plurality of button K, weighing sensor, enlarged module, AD converter, digital processing circuit and display are consecutive, button and memory all link to each other with digital processing circuit, enlarged module cascade by a AD620 of amplifier for the appearance and an operational amplifier OP07 and form, the appearance uses amplifier AD620 and operational amplifier OP07 all to connect the mode as inverting amplifier, button K's first end DC power supply anodal vcc, button K's second termination ground is connect through pull -up resistance R0, button K's first termination digital processing circuit's signal input part. This an instrument of weighing for metal material fatigue damage test easy to carry out, measurement accuracy is high.

Description

A kind of weighing instruments for Fatigue Damage of Metal test

Technical field

The utility model relates to a kind of weighing instruments for Fatigue Damage of Metal test.

Background technology

Adopt hydrometer method to come, in the process of measuring metallic materials fatigue damage, to need the quality of measuring metallic materials sample, existing weighting device structure is complicated, cost is high, and measuring accuracy does not reach the requirement of experiment, therefore, be necessary to design a kind of novel weighing device.

Utility model content

Technical problem to be solved in the utility model is to provide a kind of weighing instruments for Fatigue Damage of Metal test, and this weighing instruments being used for Fatigue Damage of Metal test is easy to implement, and measuring accuracy is high.

The technical solution of utility model is as follows:

For a weighing instruments for Fatigue Damage of Metal test, comprise LOAD CELLS, amplification module, A/D converter, digital processing circuit, storer, display and multiple button K;

LOAD CELLS, amplification module, A/D converter, digital processing circuit are connected successively with display; Button is all connected with digital processing circuit with storer;

Described amplification module is formed by an an instrumentation amplifier AD620 and operational amplifier OP07 cascade; Instrumentation amplifier AD620 and operational amplifier OP07 are all connected for sign-changing amplifier pattern;

The first end of described button K meets DC power anode Vcc by pull-up resistor R0, the second end ground connection of button K; The signal input part of the first termination digital processing circuit of button K.

Described A/D converter adopts 16 bit A/D converter chip AD976A.

Described display is LCDs.

The output signal of LOAD CELLS connects the reverse input end of instrumentation amplifier AD620, between 1 pin of instrumentation amplifier AD620 and 8 pin, cross-over connection has gain setting resistor RG, the output terminal of instrumentation amplifier AD620 connects the reverse input end of operational amplifier OP07 by resistance R21, between the reverse input end of operational amplifier OP07 and output terminal, cross-over connection has resistance R23; The output terminal of operational amplifier OP07 is the output terminal of amplification module, the input end of the output termination A/D converter of amplification module.

Digital processing circuit is existing proven technique, digital device can be adopted to build, also can adopt integrated process chip, as single-chip microcomputer and DSP etc., when adopting the integrated device such as single-chip microcomputer or DSP, does not relate to progresses and methods.

Beneficial effect:

Weighing instruments for Fatigue Damage of Metal test of the present utility model adopts instrumentation amplifier AD620 as pre-amplifier, simple circuit, adopt OP07 as post-amplifier, amplified by faint signal, and adopt the A/D converter of 16 to carry out analog-digital conversion, thus measuring accuracy is high, in addition, the parts adopted are the parts of conventional maturation, and easy to implement, cost is low.

Accompanying drawing explanation

Fig. 1 is the overall circuit block diagram of the weighing instruments for Fatigue Damage of Metal test;

Fig. 2 is key circuit schematic diagram;

Fig. 3 is the circuit theory diagrams of amplification module.

Embodiment

Below with reference to the drawings and specific embodiments, the utility model is described in further details:

As Figure 1-3, a kind of weighing instruments for Fatigue Damage of Metal test, comprises LOAD CELLS, amplification module, A/D converter, digital processing circuit, storer, display and multiple button K;

Described A/D converter adopts 16 bit A/D converter chip AD976A.

Described display is LCDs.

In Fig. 2, when button K does not press, P30 place is high level (Vcc), and when button K presses, P30 place ground connection is low level, and whether this circuit can detect button K and press thus.

This key circuit is multiple, and at least one measures button and a heavy button of unhairing.

In Fig. 3,2 operational amplifier A 1 and A2, all as sign-changing amplifier, adopt different resistance configuration, can obtain different enlargement factors, and after cascade, this amplifier is still forward amplifying circuit.

For AD620, the computing method of its enlargement factor are Uo1/Ui=-(1+49.4k/RG);

For OP01, its enlargement factor is Uo/Uo1=-R23/R21.

The measuring process of this weighing device is used to be: first to claim gross weight, then unhairing key is pressed, weight to be measured is put in display screen prompting, after weight is put into, press measurement key again, then the weight now recorded deducts the weight (concrete subtraction is performed by the subtracter in digital processing circuit) that gross weight is weight, and the weight of weight shows in the display, for reading, namely complete one-shot measurement.

Claims

1., for a weighing instruments for Fatigue Damage of Metal test, it is characterized in that, comprise LOAD CELLS, amplification module, A/D converter, digital processing circuit, storer, display and multiple button K;

2. the weighing instruments for Fatigue Damage of Metal test according to claim 1, it is characterized in that, described A/D converter adopts 16 bit A/D converter chip AD976A.

3. the weighing instruments for Fatigue Damage of Metal test according to claim 1 and 2, it is characterized in that, described display is LCDs.

4. the weighing instruments for Fatigue Damage of Metal test according to claim 3, it is characterized in that, the output signal of LOAD CELLS connects the reverse input end of instrumentation amplifier AD620, between 1 pin of instrumentation amplifier AD620 and 8 pin, cross-over connection has gain setting resistor RG, the output terminal of instrumentation amplifier AD620 connects the reverse input end of operational amplifier OP07 by resistance R21, between the reverse input end of operational amplifier OP07 and output terminal, cross-over connection has resistance R23; The output terminal of operational amplifier OP07 is the output terminal of amplification module, the input end of the output termination A/D converter of amplification module.