CN203477549U - Programmable controller-based pulse solenoid valve control circuit - Google Patents

Abstract

The utility model discloses a pulse solenoid valve control circuit based on a programmable controller, comprising a power-off protection circuit, a single-chip microcomputer capable of generating a control pulse signal and a positive pulse signal, two moving contacts connected in series with the output of the positive pulse signal The double-pole double-throw relay is an electronic switch that is connected to the control pulse signal output and can be controlled to make the double-pole double-throw switch act. The normally closed contacts on the side are respectively communicated with the positive pole of the pulse solenoid valve, and the normally closed contacts on the negative pole side and the normally open contacts on the positive pole side of the double pole double throw relay are respectively communicated with the negative pole of the pulse solenoid valve. The utility model utilizes the pulse reverse function of the double-pole double-throw relay, which can realize the double-action control of a positive pulse output to the pulse solenoid valve, simplifies the circuit design, and at the same time can conveniently control the solenoid valve on the existing design. Replacement, low cost and corresponding improvement is small, easy to implement.

Description

Pulse Solenoid Valve Control Circuit Based on Programmable Controller

technical field

The utility model relates to the technical field of electric control, in particular to a pulse electromagnetic valve control circuit based on a programmable controller. the

Background technique

In automation control, such as washing machines, dishwashers, etc., solenoid valves are widely used. Now the common solenoid valves generally use commercial power or industrial power. The current flows through the solenoid wire package to generate a magnetic field, which attracts the valve core to realize closing or opening. . During the working process, the electromagnetic wire package is energized for a long time, which is very easy to generate high temperature or even burn the wire package to cause accidents; in a high temperature and humid environment, ordinary solenoid valves are more prone to failure and leakage; when there is a power shortage or power failure, ordinary solenoid valves cannot work , if other power sources are used, there are a series of problems such as power supply and line installation due to the large power consumption of ordinary solenoid valves. the

Compared with ordinary solenoid valves, pulse solenoid valves are gradually replacing solenoid valves due to their many advantages. The advantages of pulse solenoid valves are:

1. Energy saving, the pulse voltage required by the pulse valve is 12V, the pulse width is 80ms, and the instantaneous power is 2.88 watts. As for the MFJ0-3 type AC valve electromagnet, its starting power is 310 watts and its holding power is 45 watts. Taking 1 minute as a working cycle, the energy consumption ratio of the pulse valve and the AC solenoid valve is 1:11178. the

2. Low noise, there is only a slight noise when the pulse valve is turned on or off, but there will be a continuous loud hum when the AC solenoid valve is turned on. the

3. Almost no heat, the pulse valve has almost no heat, and the heat generated by the control circuit board is also very small. However, due to the high voltage and high power of the AC solenoid valve, its electromagnet and control circuit board will continue to generate heat during work. the

Although some electrical appliances, such as the control circuit of a fully automatic washing machine with a single-chip microcomputer, output 12V direct current to the control circuit of the solenoid valve, the solenoid valve is turned on when the power is turned on; The ratio of the pulse solenoid valve is still very high, and if the control of the pulse solenoid valve is realized by a single-chip microcomputer, it becomes an urgent problem to be solved. the

Utility model content

The purpose of the utility model is to provide a programmable controller-based pulse solenoid valve control circuit with simple structure and stable control in view of the technical defects in the prior art. the

The technical scheme adopted for realizing the purpose of this utility model is:

A pulse solenoid valve control circuit based on a programmable controller, including a power-off protection circuit, a single-chip microcomputer that can generate a control pulse signal and a positive pulse signal, and a double-pole double-throw relay with two moving contacts connected in series with the positive pulse signal output , an electronic switch that is connected to the output of the control pulse signal and can be controlled to make the double-pole double-throw switch act, wherein the normally open contact on the positive side of the double-pole double-throw relay and the normally closed contact on the negative side The points are respectively communicated with the positive pole of the pulse solenoid valve, and the normally closed contact on the negative pole side and the normally open contact on the positive pole side of the double pole double throw relay are respectively communicated with the negative pole of the pulse solenoid valve. the

The electronic switch includes a first capacitor C1, a second capacitor C2, a switching transistor T1, a first resistor R _B and a second resistor R _C , and the source of the switching transistor T1 is connected in series with the first capacitor C1 to the microcontroller. Control pulse output connection, one end of the first resistor _RB is connected to the positive pole of the power supply, and the other end is connected between the first capacitor C1 and the source, and the gate of the switching transistor T1 is connected in series with the resistor Rc to the positive pole of the power supply. At the same time, the gate of the switching transistor is also connected in series with the second capacitor C2 and the coil of the double-pole double-throw relay to be grounded, and the drain of the switching transistor is grounded.

A control method of a pulse solenoid valve control circuit as claimed in claim 1, comprising the following steps,

1) The single-chip microcomputer outputs a control pulse signal to the electronic switch to make it open and drive the double-pole double-throw switch action to connect the pulse solenoid valve with the positive pulse signal output terminal of the single-chip microcomputer in a short time;

2) The microcontroller outputs at least two positive pulse control signals to drive the pulse solenoid valve to open;

3) When the pulse solenoid valve needs to be closed, the single-chip microcomputer controls the electronic switch to close so that the pulse solenoid valve is in reverse communication with the positive pulse signal output end of the single-chip microcomputer, and then the single-chip microcomputer outputs at least two positive pulses to drive the pulse solenoid valve to close. the

It also includes the step of turning off the electronic switch by the single-chip microcomputer to make the pulse solenoid valve communicate with the positive pulse signal output end of the single-chip microcomputer in reverse, and the power-off protection circuit outputs at least two positive pulses through the single-chip microcomputer to drive the pulse solenoid valve to close. the

It also includes the step of sending at least two positive pulses to the pulse valve through the relay immediately after the power is turned on, so as to ensure the initial closing of the pulse valve. the

Compared with the prior art, the beneficial effects of the utility model are:

The utility model utilizes the pulse reverse function of the double-pole double-throw relay, which can realize the double-action control of a positive pulse output to the pulse solenoid valve, simplifies the circuit design, and at the same time can conveniently control the solenoid valve on the existing design. Replacement, low cost and corresponding improvement is small, easy to implement, and can effectively realize the advantages of the pulse solenoid valve. the

Description of drawings

Fig. 1 shows that the control circuit solenoid valve of the present utility model opens the instantaneous current flow diagram;

Fig. 2 shows that the control circuit solenoid valve of the present utility model closes the momentary current flow schematic diagram;

Detailed ways

Below in conjunction with accompanying drawing and specific embodiment the utility model is described in further detail. It should be understood that the specific embodiments described here are only used to explain the utility model, and are not intended to limit the utility model. the

As shown in Figures 1 and 2, the pulse solenoid valve control circuit based on the programmable controller of the present invention includes a power-off protection circuit, a single-chip microcomputer that can generate a control pulse signal and a positive pulse signal, two moving contacts and the positive pulse signal The double-pole double-throw relay output in series is an electronic switch that is connected to the control pulse signal output and can be controlled to make the double-pole double-throw switch act, wherein the normally open contact on the positive side of the double-pole double-throw relay The normally closed contacts on the negative side and the negative pole side are respectively communicated with the positive pole of the pulse solenoid valve, and the normally closed contacts on the negative pole side of the double pole double throw relay and the normally open contacts on the positive pole side are respectively communicated with the negative pole of the pulse solenoid valve . Wherein, the power-off protection circuit can adopt the existing technology, such as the design of the existing automatic washing machine, which will not be repeated here. For the single-chip microcomputer, any model can be used, as long as simple programming is carried out, the purpose of the utility model can be realized. If the power margin of the power-off protection circuit is insufficient, connect a capacitor in parallel with the original power-off protection circuit capacitor of the washing machine or increase the original capacitance. the

Utilizing the pulse reverse function of the double-pole double-throw relay, a positive pulse output can be used to control the double action of the pulse solenoid valve, which simplifies the circuit design, and at the same time, it is convenient to replace the solenoid valve on the existing design, and the cost is low. Low and the corresponding improvement is small, easy to implement, and can effectively realize the advantages of pulse solenoid valves. the

As a preferred solution, the electronic switch includes a first capacitor C1, a second capacitor C2, a switch transistor T1, a first resistor R _B and a second resistor R _C , and the source of the switch transistor T1 is connected in series with the first capacitor C1 Afterwards, it is connected to the control pulse output of the single-chip microcomputer, one end of the first resistor _RB is connected to the positive pole of the power supply (Ucc), and the other end is connected between the first capacitor C1 and the source, and the gate series resistor of the switching transistor T1 Rc is then connected to the positive pole of the power supply, and at the same time, the gate of the switch transistor is also connected in series with the second capacitor C2 and the coil of the double-pole double-throw relay, and then grounded, and the drain of the switch transistor is grounded. The structure of the electronic switch circuit adopted by the utility model is simple and mature, because the single-chip microcomputer can only directly output a short-term continuous voltage of 5V, so the relay action can be realized through the electronic switch circuit and requires a short-term (about 1-2 seconds) continuous voltage of 12V. Then complete the pulse output.

Among them, the working principle of the pulse solenoid valve: the pulse solenoid valve is composed of a solenoid coil, a permanent magnet, a valve stem, a spring, a valve core and a valve body. Its function is to control the on-off of the water flow under the action of the pulse signal. When the positive pulse signal is input, the magnetic field of the electromagnetic coil and the permanent magnet cancel each other, and the valve stem pushes the valve core to move under the spring force to close the valve port; when the reverse pulse signal is input, the magnetic field of the electromagnetic coil and the permanent magnet interact with each other. Superimposed, the valve stem sucks the valve core back under the action of the magnetic force, opening the valve port. After the valve stem is opened or closed, it is held in the open or closed position by the magnetic force of the permanent magnet. the

The working process of the pulse solenoid valve control circuit of the present utility model is as follows:

1) As shown in Figure 1, the single-chip microcomputer outputs a control pulse signal to the electronic switch to turn it on and drive the double-pole double-throw switch action to connect the pulse solenoid valve with the positive pulse signal output terminal of the single-chip microcomputer for a short time;

2) The microcontroller outputs at least two positive pulse control signals to drive the pulse solenoid valve to open;

3) As shown in Figure 2, when the pulse solenoid valve needs to be closed, the single-chip microcomputer controls the electronic switch to close so that the pulse solenoid valve is in reverse communication with the positive pulse signal output end of the single-chip microcomputer, and then the single-chip microcomputer outputs at least two positive pulses to drive the pulse solenoid valve closure. the

As a preferred solution, it also includes that the single-chip microcomputer closes the electronic switch so that the pulse solenoid valve is connected to the positive pulse signal output end of the single-chip microcomputer in reverse and the power-off protection circuit outputs at least two positive pulses through the single-chip microcomputer to drive the pulse solenoid valve to close. The first step is to use the existing power-off protection circuit to simply realize the power-off shutdown of the pulse solenoid valve, which improves the safety of the solenoid valve. the

As a preferred solution, it also includes the step of sending at least two positive pulses to the pulse valve through the relay immediately after the power is turned on, so as to ensure the initial closing of the pulse valve, and the self-checking closure of the pulse solenoid valve when the power is turned on further improves its use. stability. the

The above is only a preferred embodiment of the utility model, it should be pointed out that for those of ordinary skill in the art, without departing from the principle of the utility model, some improvements and modifications can also be made, these Improvement and retouching should also be regarded as the protection scope of the present utility model. the

Claims (2)

1. A pulse solenoid valve control circuit based on a programmable logic controller, characterized in that it comprises a power-off protection circuit, a single-chip microcomputer that can produce a control pulse signal and a positive pulse signal, and two movable contacts are connected in series with the positive pulse signal output The double-pole double-throw relay is an electronic switch that is connected to the control pulse signal output and can be controlled to make the double-pole double-throw switch act, wherein the normally open contact on the positive side of the double-pole double-throw relay and The normally closed contacts on the negative side are respectively communicated with the positive pole of the pulse solenoid valve, and the normally closed contacts on the negative pole side and the normally open contacts on the positive side of the DPDT relay are respectively communicated with the negative pole of the pulse solenoid valve. the 2. The pulse solenoid valve control circuit according to claim 1, wherein said electronic switch comprises a first capacitor C1, a second capacitor C2, a switching transistor T1, a first resistor R _B and a second resistor R _C , the source of the switching transistor T1 is connected in series with the first capacitor C1 to the control pulse output of the microcontroller, one end of the first resistor R _B is connected to the positive pole of the power supply, and the other end is connected between the first capacitor C1 and the source , the gate of the switching transistor T1 is connected to the positive pole of the power supply after being connected in series with the resistor Rc, and at the same time, the gate of the switching transistor is also connected in series with the second capacitor C2 and the coil of the double-pole double-throw relay in sequence, and then grounded, The drain of the switching transistor is grounded.

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