CN1848016A

CN1848016A - Electric Proportion valve controlling circuit

Info

Publication number: CN1848016A
Application number: CN 200510025101
Authority: CN
Inventors: 潘承农
Original assignee: SHANGHAI WEISHI MECHANICS CO Ltd
Current assignee: SHANGHAI WEISHI MECHANICS CO Ltd
Priority date: 2005-04-15
Filing date: 2005-04-15
Publication date: 2006-10-18
Anticipated expiration: 2025-04-15
Also published as: CN100474202C

Abstract

The electric proportion valve controlling circuit includes: one sensor assembly for pre-amplifying, temperature compensation, A/D conversion, D/A conversion and outputting voltage signal proportional to the measured pressure; one central control circuit with built-in A/D converter, reference circuit, clock circuit, etc. to receive the measured voltage signal from the sensor assembly and the setting signal from outer regulator for A/D conversion, scale conversion and PID control operation so as to output digital signal for output module to execute regulation function; one switching power source module to provide high quality low voltage power source; and one driving output module to receive the digital signal from the microprocessor to regulate the output pressure proportional to the input electric signal. The present invention is simple, reliable, and low in cost.

Description

A kind of electric Proportion valve controlling circuit

Technical field

The present invention relates to a kind of electric Proportion valve controlling circuit, electric Proportion valve often is applied to weaving, chemical industry, garment machinery and the control of other industrial processs.

Background technology

Electric Proportion valve is a kind of air pressure regulator by electric energy control of precision.Its working mechanism is proportional for the electric signal of the atmospheric pressure that keeps output and input.Output pressure is regulated in open and close with two high-frequency electromagnetic valves, is one of method that realizes this function.After input electrical signal is determined, whether control circuit will be measured output pressure and meet with it, if output is higher than setting, then open vent valve, to reduce output pressure; If output is lower than set pressure, then open gas admittance valve, to improve output pressure; If output pressure equates that with setting then gas admittance valve and vent valve are all closed, if system does not consume air-flow, even power supply disconnects, pressure also keeps.

Electric Proportion valve often is applied to weaving, chemical industry, garment machinery and the control of other industrial processs.Because traditional electric Proportion valve complex structure, components and parts are intensive, and often continuous working is under the environment of high temperature, high humidity, requirement to design level and manufacture craft level is all very high, cleanliness requirement to the work source of the gas is also very harsh, makes it be difficult to popularize and cost an arm and a leg on broader applications.At present domestic also do not have producer producing in batches.

One of gordian technique of electric Proportion valve is sensor and amplifying circuit.

Pressure transducer also has various ways, and the pressure transducer that is adapted at using on the electric Proportion valve must possess characteristics such as volume is little, broad quantum, precision height, the linearity is good, temperature stability is good, the life-span is long.Once had similar sensor to adopt the laser calibration technology, but follow-up differential amplifier circuit is also quite complicated.Because the inevitable discreteness of discrete device must carefully be adjusted each link in the production run, make production cost improve, quality but is difficult to guarantee.

Two of the gordian technique of electric Proportion valve is microprocessors.

Microprocessor is the heart of electric Proportion valve, handle the switching value output signal from the given signal of signal, the regulator of sensor and amplifier, auxiliary input signal, auxiliary output signal and numeral.Require processor to have the AD/DA translation function, at a high speed, features such as highly reliable and microminiaturization.

Traditional electric Proportion valve generally adopts inside to be integrated with 8 single-chip microcomputers of AD conversion, and resolution also often has only 8, and travelling speed is not high yet.Make the performance or the cost performance of proportioning valve be subjected to certain restriction.

Summary of the invention

In view of the deficiency of existing electric Proportion valve, the object of the present invention is to provide a kind of simple in structure, performance improves, easy to make and electric Proportion valve controlling circuit that cost reduces.

A kind of electric Proportion valve controlling circuit provided by the present invention, comprise sensor element, the first attenuation filter circuit, the second attenuation filter circuit, switch power module, central control circuit, linear voltage-stabilized power supply circuit and driving output module, it is characterized in that: sensor element links to each other with the first attenuation filter circuit, central control circuit respectively with the first attenuation filter circuit, the second attenuation filter circuit links to each other with the driving output module, linear voltage-stabilized power supply circuit links to each other with the driving output module with the second attenuation filter circuit respectively, switch power module links to each other with sensor element with central control circuit respectively, wherein: sensor element, be used for preposition amplification, temperature compensation and A/D, functions such as D/A conversion, directly output and the proportional voltage signal of institute's measuring pressure; The first attenuation filter circuit after decay, is sent to central control circuit with the voltage signal of sensor element output; The second attenuation filter circuit will be sent to central control circuit from the setting voltage of external regulator filter or current signal after buffering; Central control circuit, control function with built-in entirely A/D conversion, reference voltage, clock circuit, house dog and PWM, reception is from the output voltage signal of the first attenuation filter circuit with from the output voltage signal of the second attenuation filter circuit, after two signals are carried out computing decision-making, with switching value form output digital signal, carry out regulatory function for driving output module; Drive output module,, be used to open or close solenoid valve at a high speed, regulate the output pressure of proportioning valve, make that output pressure and input electrical signal are proportional according to the output digital signal of central control circuit; Switch power module is converted to the low-tension supply of setting value with the direct supply of external perimysium reference voltage with the DC/DC on-off mode, and microprocessor and sensor are given in power supply; Linear voltage-stabilized power supply circuit, power supply, the setting signal total with the outside are connected, and linear stabilized power supply is provided, to first, second attenuation filter circuit supply.

Adopted above-mentioned technical solution, the present invention utilizes high integrated circuit block to realize the foolproof electric Proportion valve of a kind of structure, and it is also simple relatively that it manufactures process, dependable performance, production cost also can descend significantly, has very high cost performance.

Description of drawings

Fig. 1 is the schematic diagram of electric Proportion valve controlling circuit of the present invention.

Embodiment

As shown in Figure 1, electric Proportion valve controlling circuit of the present invention comprises sensor element 1, the first attenuation filter circuit 2, the second attenuation filter circuit 3, switch power module 5, central control circuit 4, linear voltage-stabilized power supply circuit 6 and drives output module 7.

Sensor element 1 is used for functions such as preposition amplification, temperature compensation and A/D, D/A conversion, directly output and the proportional voltage signal of institute's measuring pressure (0.5-4.5V).Can adopt the ASDX series of U.S. Honeywell (HONEYWELL), high integrated pressure transducer U1 is suitable for pressure limit 0-100PSI (about 0.7MPA).

The first attenuation filter circuit 2, the voltage signal of receiving sensor parts 1 output being sent to central control circuit 4 after the voltage signal decay of sensor output, is connected with the AD0 passage of microprocessor U2.The first attenuation filter circuit is made up of one of dual operational amplifier U5 U5/B and R1, C3, and wherein can to adopt the model of MOTOROLA company be the chip of LM358 to operational amplifier U5/B.

The second attenuation filter circuit 3, from external regulator filter (can be a control system, also can be a simple potentiometer) setting signal (0-10V voltage or 4-20MA electric current), on input resistance R4 and filter capacitor C4, produce voltage signal, cushion through operational amplifier U5/A operational amplifier, resistance R 2 decay, capacitor C 7 filtering enter the AD1 passage of microprocessor U2.Wherein operational amplifier U5/A and U5/B are same chip piece.

Central control circuit 4, has complete built-in A/D conversion, reference voltage, clock circuit, house dog and PWM control function such as (width modulation outputs), reception is from the AD0 channel voltage signal of the first attenuation filter circuit 2 with from the setting signal of the AD1 passage of the second attenuation filter circuit 3, by the fixed clock cycle of timer internal generation, microprocessor U 2 drives output module 7 by OUT0 and OUT1 two radical word output lines after these signals are carried out 10 AD conversions (traditional proportioning valve adopts 8 AD conversion), scale transformation, PID computing.This central control circuit 4 is that microprocessor U2 (having adopted the ATMEGA8 single-chip microcomputer (version of the enhancement mode C8051F330 single-chip microcomputer of U.S. SILICON LABS company) of American ATMEL) is arranged, add few peripheral component (resistance R 3, inductance L 1, capacitor C 1 and C2, wherein: L1 is the inductance of one 100 microhenry, form filtering circuit with C2, improve the stability of analog power, R3 is used for the chip reliable reset, C1 is used for stablizing internal reference voltage) form, to satisfy above-mentioned control requirement.

Drive output module 7, by solenoid valve J1, J2, triode T1, T2, diode D2, D3, resistance R 5, R6, capacitor C 8 forms U4, J1 is connected the coil of solenoid valve with J2, afterflow when D2, D3 are used for the solenoid valve shutoff.C8 is used for the 24V power filter.It is according to the output signal of central control circuit, that is: when OUT0 be output as high level, when OUT1 is low level, solenoid valve J1 dead electricity is closed, flow through the electric current of resistance R 6, make triode T2 conducting, the J2 pressure-releasing electromagnetic valve gets electric, has the gas of pressure to discharge to outside atmosphere in the valve body, reaches the purpose that reduces the proportioning valve output pressure; When control decision allows the OUT1 be that high level, OUT0 are low level, then the J2 pressure-releasing electromagnetic valve is closed, J1 inflation solenoid valve is opened, and external air source (bleed pressure be higher than proportioning valve more than the high output pressure 0.1MP) to the proportioning valve inflation, makes the output pressure of proportioning valve raise; When OUT0 and OUT1 output low level all, then two valves are all closed.Control these output high level shared time width in each cycle, fine degree and the stability that can regulate output pressure.Solenoid valve J1, J2 can adopt German NAIS high frequency pilot valve.It is little to have volume, and response is fast, advantages such as low price.Cooperating does not have the structure of amplifying gas circuit, is applicable to the load of low capacity.If drive bigger cylinder or air bag, then need to cooperate valve seat with air-flow enlarging function.Another one embodiment of the present invention has adopted the heavy caliber high-frequency electromagnetic valve of U.S. MAC company, and the simple valve seat that uses airless to amplify just can satisfy very most application, has both improved reliability, has also reduced production cost.

Switch power module 5 is the low-tension supply of 5V or 3V with the 24V power source conversion of outside, uses for microprocessor and sensor.This switch power module has the efficient height, volume is little, do not generate heat, respond characteristics such as fast, and an important technology index of electric Proportion valve is exactly in case outage in the work requires output pressure still can remain unchanged, the fast-response of this programme can satisfy this requirement, and the general linear circuit just is difficult to accomplish.The model of these switch power module 5 usefulness MOTOROLA companies is 34063DC/DC switch chip U3.

Linear voltage-stabilized power supply circuit 6, power supply, the setting signal total with the outside are connected, and by the linear voltage-stabilizing circuit that U6, capacitor C 5 and C6 form, obtain the burning voltage of 12V from the 24V power supply, power to operational amplifier U5.Wherein diode D1 prevents that electric power polarity from connecing and damages other circuit on the contrary.It is the microchip of 78L12 that U6 can adopt model.

In sum, the present invention has adopted high integrated sensor element, has avoided the precision that small-signal amplifies on the Application Design and the difficult point of temperature stability; Its 10 built-in high-speed A/D converters of the microprocessor of central control circuit make the single-chip microcomputer of its resolution far above 8 traditional bit resolutions, the program space of 8K FLASH, allow the user to adopt advanced language programming, can improve program quality greatly, shorten the development time; Switch power module has obtained high-quality low-tension supply, and the efficient height, and volume is little, does not generate heat; Drive output module and adopt the high frequency pilot valve, it is little to have a volume, and response is fast, advantages such as low price.Especially electric Proportion valve has an important indicator to be exactly in case outage in the work requires air pressure still to remain unchanged, and the present invention can accomplish this point, and the general linear circuit just is difficult to accomplish.

More than pass through embodiment; design concept and basic structure to electric Proportion valve controlling circuit of the present invention illustrate; so protection scope of the present invention is not limited to the foregoing description; under the situation that does not break away from essence spirit of the present invention and principle, change any equivalence and similar all comprises within the scope of the present invention.

Claims

1. electric Proportion valve controlling circuit, comprise sensor element, the first attenuation filter circuit, the second attenuation filter circuit, switch power module, central control circuit, linear voltage-stabilized power supply circuit and driving output module, it is characterized in that: sensor element links to each other with the first attenuation filter circuit, central control circuit respectively with the first attenuation filter circuit, the second attenuation filter circuit links to each other with the driving output module, linear voltage-stabilized power supply circuit links to each other with the driving output module with the second attenuation filter circuit respectively, switch power module links to each other with sensor element with central control circuit respectively, wherein:

Sensor element is used for functions such as preposition amplification, temperature compensation and A/D, D/A conversion, directly output and the proportional voltage signal of institute's measuring pressure;

The first attenuation filter circuit after decay, is sent to central control circuit with the voltage signal of sensor element output;

The second attenuation filter circuit will be sent to central control circuit from the setting voltage of external regulator filter or current signal after buffering;

Central control circuit, control function with built-in entirely A/D conversion, reference voltage, clock circuit, house dog and PWM, reception is from the output voltage signal of the first attenuation filter circuit with from the output voltage signal of the second attenuation filter circuit, after two signals are carried out computing decision-making, with switching value form output digital signal, carry out regulatory function for driving output module;

Drive output module,, be used to open or close solenoid valve at a high speed, regulate the output pressure of proportioning valve, make that output pressure and input electrical signal are proportional according to the output digital signal of central control circuit;

Switch power module is converted to the low-tension supply of setting value with the direct supply of external perimysium reference voltage with the DC/DC on-off mode, and microprocessor and sensor are given in power supply;

Linear voltage-stabilized power supply circuit, power supply, the setting signal total with the outside are connected, and linear stabilized power supply is provided, to first, second attenuation filter circuit supply.