CN201535793U - Keyboard type pre-payment three-phase electric energy meter - Google Patents

Abstract

The utility model discloses a keyboard type pre-payment three-phase electric energy meter, which comprises a single chip microcomputer and a push button unit, wherein the push button unit consists of a thin film switch and an insulation circuit thereof, and the insulation circuit is connected with the single chip microcomputer, and is used to send data input by the thin film switch to the single chip microcomputer. The insulation circuit of the push button unit is mainly composed of a photoisolator, a thermo-sensitive resistor and a power supply. The keyboard type pre-payment three-phase electric energy meter can integrate functions of a panel and a switch, saves a touch switch, carbon oil and a printing circuit board thereof in the meter, lowers the material cost of the electric energy meter, has small volume and flexible push button design, and can be conveniently adjusted according to demands and favor of clients, thereby matching with demands of different applications.

Description

Keyboard-type pre-payment three-phase electric energy meter

Technical field

The utility model relates to a kind of electric energy measurement instrument, relates in particular to a kind of keyboard-type pre-payment three-phase electric energy meter.

Background technology

Prepayment meter has in the market adopted various media, CPU card, logic encryption card, Electrical key, virtual medium etc. are arranged, wherein a kind of mode obtains the string number sign indicating number for the back of paying, sometimes also be token TOKEN, carry out the prepaid data transmission by the numeric keypad on the ammeter, because the keyboard that its mode of supplementing with money adopts electric energy meter to carry carries out, and is commonly referred to the keyboard-type prepayment meter.Have at present above up to ten million the keyboard prepayment meters that meet STS standard (standard transmission standard) and be installed in more than 30 more than 400 national Utilities Electric Co..

The materials that button that these keyboard pre-paying kilowatt-hour meters are adopted great majority use are conductive rubber or touch-switch, and the shortcoming of existence mainly contains easily and wear out, is difficult to sealing, water proof and dust proof poor performance, serviceable life than lacking etc.From manufacturing unit, needing separately be last box and button mold developing, has both invested greatlyyer, and the cycle is longer again, and profile also is difficult for variation, and button is more is not easy to assembling in enormous quantities, and production efficiency is lower.

The utility model content

The purpose of this utility model is the deficiency that exists at existing keyboard prepayment meter, provide a kind of reliability that can improve keyboard and adaptability, reduction ammeter cost, reduce the keyboard-type pre-payment three-phase electric energy meter of construction cycle.

This keyboard-type pre-payment three-phase electric energy meter that the utility model provides, comprise single-chip microcomputer, push-button unit, described push-button unit is made up of thin film switch and buffer circuit thereof, and buffer circuit is connected with single-chip microcomputer, is used for the data of thin film switch input are delivered to single-chip microcomputer.

The buffer circuit of described push-button unit mainly is made up of photoisolator, thermistor and power supply.

Because the utility model has adopted thin film switch, can integrate panel and switching function, saved touch-switch, carbon oil and the printed circuit board thereof in the table, reduced the ammeter material cost.

Thin film switch is the plastic electronic goods that integrate figure, button, label symbol demonstration, conduction and electronic switch function of many planes combination sealing of being made of utilization screen printing technique, and the main characteristics of applied film switch are on ammeter:

1, small volume and less weight, thin film switch weight are gram surplus in the of ten only, and are an integral body, are mounted on during installation on the lower panel of ammeter, are convenient to very much produce in enormous quantities;

2, attractive in appearance: as to have adopted modern silk-screen technology, can arrange in pairs or groups and go up suitable layout;

3, sealing: the thin film switch water proof and dust proof of this table, grease proofing, anti-pollution, anticorrosion;

4, electric conductivity is good: the internal switch circuit adopts printings such as copper platinum, can not damage after conductive layer is folding; And resistance can be controlled;

5, cost is low: its price advantage is that other like product is unattainable;

6, long service life: because the material that thin film switch adopted has good insulation performance, thermotolerance, fold resistance and higher resilience; And back face printing is all adopted in the printing of pattern, makes screen printing pattern unlikely impaired; Thin film switch generally can reach more than 500,000 times serviceable life;

7, flexible design: can adjust very easily according to customer requirement and hobby, to cooperate needs of different applications.

Description of drawings

Fig. 1 is a structural representation of the present utility model.

Embodiment

The utility model still comprises single-chip microcomputer and keyboard unit as can be seen from Figure 1, and what big keyboard unit adopted is thin film switch and buffer circuit thereof, and buffer circuit is connected with single-chip microcomputer, is used for the data of thin film switch input are delivered to single-chip microcomputer.The buffer circuit of push-button unit mainly by photoisolator NY1 ~ NY8, thermistor RTP7 ~ 10 and power supply V3P3 ,+5V forms.When whether the single-chip microcomputer detection has button to press, from output port KEY_OUT1～KEY_OUT4 output low level, this moment photoisolator NY1 ~ NY4 diode current flow, the collector output low level outputs to thin film switch by thermistor RTP7 ~ 10 again, if the button on the thin film switch is pressed, corresponding diode will conducting among photoisolator NY4 ~ NY8, the collector output low level also is a low level by corresponding input end mouth KEY_IN1 ~ KEY_IN4, is arrived by the monolithic machine testing; If there is not button to press, all not conductings of diode of correspondence among photoisolator NY4 ~ NY8, the 4th pin is all exported high level, and input port KEY_IN1 ~ KEY_IN4 is high level, and single-chip microcomputer will be judged does not have button to press this moment.

Thin film switch mainly is made up of facial mask, facial mask gum, last circuit, separation layer, following circuit and gum.Wherein face mask layer, last line layer, following line layer are transparent membranes, and the main material that adopts is PC, PET, PVC, and facial mask gum, separation layer and gum layer material are double faced adhesive tapes.When face mask layer is not pressed, separation layer plays buffer action to circuit up and down, when face mask layer is pressed, last circuit is pressed in the lump and overlaps with following circuit, make line conduction, signal after the conducting can be scanned by the single-chip microcomputer in the table by buffer circuit, and can be judged out is which key is pressed, and then realizes its function corresponding.

When the user purchased electricity, sale of electricity department provided one group to contain the digital code that the user purchases power consumption and temporal information, be made up of 20 bit digital, and through encrypting, this group digital code was called as TOKEN (token).The user is input in the ammeter by this group digital code of the thin film switch thump on the electric energy meter, and ammeter is decrypted, analyzes and confirm code, if electric weight legal then that buy is deposited in electric energy meter, has promptly realized supplementing with money electric energy meter.

The key number of thin film switch and symbol by numerical key, * key, # key and+10 ,+1 ,-1 ,-10 display keys form, wherein * key, # key are positioned at foot, the * key is positioned at the lower left corner.

Button 0～9th uses during input TOKEN, and " * " key is a delete key, and " # " key is an acknowledgement key; Keep right and use when 4 buttons (+10 ,+1 ,-1 ,-10) on limit switch display items display.After the user purchases electricity, import according to this according to the TOKEN numeral that obtains, the backlight of ammeter will be lighted during input digit, and on LCDs, show this numeral, send short song simultaneously, after whenever failing full 8 bit digital, ammeter is translated into next screen automatically, is divided into 3 screens and shows 20 TOKEN numerals; The digital number that the user has imported is pointed out out in the lower left corner of liquid crystal.After the user has imported wrong numeral because of carelessness, can use " * " key, delete last position of input digit; After having imported 20 correct TOKEN numerals, can press " # " key, ammeter will be handled the TOKEN of input: ammeter will be organized TOKEN to this and be decrypted, analyzes and judge, if the TOKEN of input is correct, electric energy meter will be carried out the order of TOKEN appointment, the symbol of LCD display operation success.If the TOKEN of input is wrong, the TOKEN that electric energy meter will can not be accepted to import, the symbol and the error code thereof of the failure of LCD display operation.

Under ammeter circulation show state, any in 4 display button on the right of pressing, backlight lightening, + 10 ,-10 key is used to change ten of reveal codes, + 1 ,-1 key is used to change a position of reveal codes ,+10 ,+1 key is used to increase reveal codes, and-10 ,-1 key is used to reduce reveal codes.

Claims (2)

1. a keyboard-type pre-payment three-phase electric energy meter comprises single-chip microcomputer, push-button unit, it is characterized in that described push-button unit is made up of thin film switch and buffer circuit thereof, and buffer circuit is connected with single-chip microcomputer, is used for the data of thin film switch input are delivered to single-chip microcomputer.

2. keyboard-type pre-payment three-phase electric energy meter according to claim 1 is characterized in that the buffer circuit of described push-button unit mainly is made up of photoisolator, thermistor and power supply.

Images