CN2179970Y

CN2179970Y - Portable digital electronic balance

Info

Publication number: CN2179970Y
Application number: CN 93245468
Authority: CN
Inventors: 施昭云; 郑旭初; 施朝华
Original assignee: Individual
Current assignee: Individual
Priority date: 1993-11-25
Filing date: 1993-11-25
Publication date: 1994-10-19
Anticipated expiration: 2003-11-25

Abstract

The utility model discloses a portable digital electronic balance, which is composed of a load-weight sensor, an electric signal processing unit, a digital display, etc., wherein, the load-weight sensor has an elastic shearing force strain beam which is additionally arranged between a balance lifting rod and a balance hanging rod; the electrical signal processing unit is composed of a signal amplifying circuit, an A/D conversion circuit and a zero clearing, shelling and weight memory circuit. During operation, a pair of tension acting on the balance lifting rod and a weight hanging rod makes the strain beam generate strain; the weight signal of a heavy object is transformed into an electric signal; finally, the weight value is displayed by the digital display after the electric signal is processed by the electric signal processing unit. The utility model has the advantages of simple structure, convenient operation, high precision, etc.

Description

Portable digital electronic balance

The utility model belongs to the measurement instrument field, particularly a kind of trading market and heavy (5～20 feather weight) portable digital electronic scales of family life amount weighing apparatus thing of being used for.

Common weighing (5～20 feather weight) utensil that present people widely use in daily life generally has steelyard, counter scale, platform balance, spring balance and electronic price computing scale etc.Steelyard, counter scale and platform balance mainly are to utilize lever construction to obtain weighing precision, and it is simple in structure, easy for operation, but weighing precision relatively poor, be not easy to carry, and on scale structure, play tricks easily; Spring balance is to adopt the spring force transferring structure to obtain weighing precision, though be convenient for carrying, low, the poor stability of its precision will not be promoted product for relevant department clearly is decided to be; Comparatively speaking, electronic price computing scale shows object loading weight with numeral, and its indicating value is clear, precision is higher, becomes the main flow of weighing apparatus development now gradually, but costing an arm and a leg, generally can only being placed on the platform case and using of electronic scales product on sale in the market can not be carried.

The purpose of this utility model is the defective according to state of the art, provide a kind of simple in structure, price is low, easy to use, indicating value accurately, can be used for replacing the portable digital electronic scales of common steelyard.

The technical solution that realizes the foregoing invention purpose is such: this portable digital electronic scales is made of load sensor, electric signal processing unit, digital indicator etc., wherein load sensor is a strain gauge transducer, and it has an elasticity shearing strain beam that is attached between scale shadoof and the scale peg; The electric signal processing unit is made up of signal amplification circuit, analog to digital conversion circuit and zero clearing, peeling and weight memory circuit.In the work, make elasticity shearing strain beam produce strain by a pair of tension force that acts on scale shadoof and the weight peg, weight of heavy is converted to electric quantity signal (voltage, electric current, frequency etc.), after this electric quantity signal process electric signal processing unit processes, finally demonstrate the value of alleged weight by digital indicator.

Compared with prior art, the utlity model has following advantage: 1. simple in structure, low price, volume be little, in light weight, be easy to carry; 2. have enough weighing precisions (accuracy value is 0.4%FS); 3. sensor response speed is fast, can improve weighing speed; Good stability, mechanical wear little, be convenient to maintenance, long service life.

Below with reference to accompanying drawing the utility model is further described.

Fig. 1 is the structural representation of a kind of load sensor form of the present utility model.

Fig. 2 is the structural representation of another kind of load sensor form of the present utility model.

Fig. 3 is a circuit working schematic diagram of the present utility model.

With reference to accompanying drawing, the structural principle of this electronic scales and common desk-top electronic scales are similar, all are that weigh is transformed into electric weight by load sensor, handle through electrical signal processing system again, are shown by numeral at last.Load sensor adopts the strain gauge transducer of being made by flexible member, and its flexible member is designed to wait shear beam structure 12, constitutes shearing formula sensor.For reducing cost, flexible member 12 adopts the section bar composite design, in concrete the enforcement, flexible member 12 can be made into as shown in Figure 1 " Jiong " type structure or " Z " type structure as shown in Figure 2.In structure shown in Figure 1, elasticity shearing strain beam 12 is a kind of " Jiong " type device of being made by elastic section bar, two elastic strain pasters (strainometer) 13,14 have been sticked in the upper edge of beam, scale shadoof 11 and scale peg 15 all are designed to a kind of rectangular-shaped member, and their horizon bar portion is contained in the above and below of strain beam 12 respectively.In structure shown in Figure 2, elasticity shearing strain beam 12 for a kind of by elastic section bar make near "

" the type device, two the elastic strain pasters (strainometer) 13,14 that have been sticked in the upper edge of beam, 15 of scale shadoof 11 and scale pegs are a kind of straight rod component, and they are installed in the above and below of strain beam 12 respectively.

Strain paster

13,14 adopts has the self-compensating strain paster of high-accuracy self-compensation, creep self compensation and elastic modulus.The electric signal processing unit is made up of signal amplification circuit 2, analog to digital conversion circuit 4 and zero clearing or peeling circuit 3.Signal amplification circuit 2 wherein is by operational amplifier A, B, Chip-

R

13,14 and resistance R ₁～R ₇, capacitor C ₁Constitute; The biproduct somatotype A/D analog to digital converter that analog to digital conversion circuit 4 is LCI7106 by a model constitutes; Zero clearing, peeling and weight memory circuit 3 are by capacitor C ₂Constitute with pushbutton switch AN.During the weighing weight, along with the deformation of shearing strain beam 12,

strain paster

13,14 is converted to electric quantity signal U with weight signal _X(see figure 3), deliver to A/D converter after amplifying through operational amplifier A again and convert digital quantity to, show with digital indicator LCD at last, the purpose that is provided with of amplifier B is to provide a kind of stable operating voltage for the operate as normal of load sensor 1 and amplifier A.When weighing, press the button AN, can realize the memory of weighing, its main value promptly was revealed and remained unchanged if take off by the thing of weighing this moment; But press the button the automatic clear of AN implement device or peeling automatically before weighing at every turn.In the utility model owing to designed zero clearing, peeling and weight memory circuit 3, make electronic scales require greatly to reduce to " the zero load output " of sensor, reduce compensation adjustment technology, the yield rate of sensor is improved greatly, also reduced cost usefulness simultaneously.

Claims

1, the heavy portable digital electronic scales of a kind of amount of being used for weighing apparatus thing is characterized in that it is by formations such as load sensor (1), electric signal processing unit, digital indicator LCD, wherein

1.1 load sensor (1) has an elasticity shearing strain beam (12) that is attached between scale shadoof (11) and the scale peg (15);

1.2 the electric signal processing unit is made up of signal amplification circuit (2), analog to digital conversion circuit (4) and zero clearing, peeling and weight memory circuit (3).

2, the portable digital electronic scales of stipulating as claim 1, it is characterized in that described elasticity shearing strain beam (12) is a kind of " Jiong " type device of being made by elastic section bar, two elastic strain pasters (13,14) have been sticked in the upper edge of beam, described scale shadoof (11) and scale peg (15) are a kind of rectangular-shaped member, and their horizon bar portion is contained in the above and below of strain beam (12) respectively.

3, as the portable digital electronic scales of claim 1 regulation, it is characterized in that described elasticity shearing strain beam (12) for a kind of by elastic section bar make near "

" the type device, two the elastic strain pasters (13,14) that have been sticked in the upper edge of beam, described scale shadoof (11) and scale peg (15) are a kind of straight bar member, and they are contained in the above and below of strain beam (12) respectively.

4,, it is characterized in that signal amplification circuit (2) in the described electric signal processing unit is by operational amplifier A, B, Chip-R (13,14) and resistance R as the portable digital electronic scaless of claim 1,2 regulations ₁～R ₇, capacitor C ₁Constitute; Analog to digital conversion circuit (4) is made of an A/D analog to digital converter; Zero clearing, peeling and weight memory circuit (3) are by capacitor C ₂Constitute with pushbutton switch AN.

5,, it is characterized in that signal amplification circuit (2) in the described electric signal processing unit is by operational amplifier A, B, Chip-R (13,14) and resistance R as the portable digital electronic scaless of claim 1,3 regulations ₁～R ₇, capacitor C ₁Constitute; Analog to digital conversion circuit (4) is made of an A/D analog to digital converter; Zero clearing, peeling and weight memory circuit (3) are by capacitor C ₂Constitute with pushbutton switch AN.