A circuit board turning machine pneumatic control circuit

Abstract

The application discloses a kind of circuit board turning machine pneumatic control circuit, including several triodes, several diodes, several field effect tubes, several resistors, the triode in the several triodes Q1 base electrode connects diode D2 cathode, resistance R2 one end, collector connects diode D1 anode, resistance R1 one end, emitter connects field effect tube Q3 drain;Triode Q2 base electrode connects diode D1 cathode, resistance R3 one end, collector connects diode D2 anode, resistance R4 one end, emitter connects field effect tube Q4 drain;Field effect tube Q3 gate connects field effect tube Q4 gate;Field effect tube Q3 source end obtains positive turning plate control signal;Field effect tube Q4 source end obtains reverse turning plate control signal;Resistance R1 other end, resistance R2 other end, resistance R3 other end, resistance R4 other end ground connection.

Description

Technical Field

[0001] This invention relates to the field of pneumatic control technology for flip-board machines, and particularly to a pneumatic control circuit for a circuit board flip-board machine. Background Technology

[0002] Circuit board flipping machines are mainly used for double-sided mounting and soldering of circuit boards, ensuring the processing accuracy of both sides and reducing damage and misalignment caused by manual operation. The flipping control of the circuit board is mainly achieved by charging the positive / reverse coils of the solenoid valve to make the cylinder extend / retract to complete the flipping of the circuit board. However, the existing pneumatic control circuit of the circuit board flipping machine may cause damage to the valve core in the solenoid valve and malfunction during flipping due to incorrect flipping control signals fed back by the MCU or manual maintenance and debugging before and during flipping. Therefore, a pneumatic control circuit for circuit board flipping machines is proposed, which can prevent damage to the valve core caused by the simultaneous energization of the positive / reverse coils in the solenoid valve before flipping and malfunction during flipping caused by the re-energization of the positive / reverse coils in the solenoid valve. It can also prevent movement deviation of the cylinder caused by air source pressure fluctuations before movement. Summary of the Invention

[0003] To address the aforementioned technical problems, the purpose of this invention is to provide a pneumatic control circuit for a circuit board flipping machine, comprising several transistors, several diodes, several field-effect transistors (FETs), and several resistors. Among the transistors, the base of transistor Q1 is connected to the cathode of diode D2 and one end of resistor R2, the collector is connected to the anode of diode D1 and one end of resistor R1, and the emitter is connected to the drain of FET Q3. The base of transistor Q2 is connected to the cathode of diode D1 and one end of resistor R3, the collector is connected to the anode of diode D2 and one end of resistor R4, and the emitter is connected to the drain of FET Q4. The gate of FET Q3 is connected to the gate of FET Q4. The source of FET Q3 receives a forward flipping control signal; the source of FET Q4 receives a reverse flipping control signal. The other ends of resistors R1, R2, R3, and R4 are grounded.

[0004] Furthermore, it also includes a trigger U2, an operational amplifier U3, and a capacitor C1. The first and fourth pins of the trigger U2, and one end of resistor R8 are connected to the power supply; the second pin is connected to the sixth pin and one end of resistor R10; the third pin is connected to the output terminal of operational amplifier U3, the cathode of diode D9, and one end of resistor R9; and the fifth pin is connected to the anode of diode D8. The non-inverting input of operational amplifier U3 is connected to one end of capacitor C1, the cathodes of diodes D3 and D4, and one end of resistor R6; the inverting input is connected to one end of resistor R7 and the other end of resistor R8. The anode of diode D3 is connected to the anode of diode D2; the anode of diode D4 is connected to the anode of diode D1; the cathode of diode D8 is connected to the gate of MOSFET Q3; the anode of diode D9 receives the flip-over completion signal; and the other ends of resistors R6, R7, R9, R10, and C1 are grounded.

[0005] Furthermore, it also includes several operational amplifiers, capacitor C2, and resistor R5. Among the several operational amplifiers, the non-inverting input of operational amplifier U1 is connected to the cathodes of diodes D5 and D6, one end of capacitor C2, and one end of resistor R5, and the output is connected to the anode of diode D7; the non-inverting input of operational amplifier U4 is connected to the inverting input of operational amplifier U5, and the output is connected to the anode of diode D6; the non-inverting input of operational amplifier U4 and the inverting input of operational amplifier U5 acquire the gas source pressure signal; the output of operational amplifier U5 is connected to the anode of diode D5; the cathode of diode D7 is connected to the cathode of diode D8; the other end of capacitor C2 and the other end of resistor R5 are grounded.

[0006] Furthermore, one end of resistor R15 is connected to the inverting input of operational amplifier U4 and one end of resistor R16, while the other end is connected to the non-inverting input of operational amplifier U5 and one end of resistor R14; the other end of resistor R16 is connected to the power supply; and the other end of resistor R14 is grounded.

[0007] Furthermore, one end of resistor R12 is connected to the power supply, and the other end is connected to the inverting input of operational amplifier U1 and one end of resistor R11; the other end of resistor R11 is grounded.

[0008] Furthermore, it also includes a resistor R13, one end of which is connected to the gate of the field-effect transistor Q3, and the other end is grounded.

[0009] Furthermore, the resistor R7 is an adjustable resistor.

[0010] Furthermore, resistors R14 and R15 are adjustable resistors.

[0011] Furthermore, the resistor R11 is an adjustable resistor.

[0012] The advantages of this invention compared to the prior art are:

[0013] This invention can prevent damage to the valve core caused by the simultaneous energization of the positive and negative coils in the solenoid valve before flipping, and prevent false flipping caused by the re-energization of the positive and negative coils in the solenoid valve during the flipping process. It can also prevent movement deviation of the cylinder caused by air source pressure fluctuations before movement. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the prior art and embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1 The circuit structure diagram provided for this invention. Detailed Implementation

[0016] To make the objectives and advantages of the present invention clearer, the present invention will be specifically described below in conjunction with embodiments. It should be understood that the following text is only used to describe one or more specific embodiments of the present invention and does not strictly limit the scope of protection specifically claimed by the present invention.

[0017] This invention discloses a pneumatic control circuit for a circuit board flipping machine, comprising several transistors, several diodes, several field-effect transistors (FETs), and several resistors. Among the transistors, the base of transistor Q1 is connected to the cathode of diode D2 and one end of resistor R2, the collector is connected to the anode of diode D1 and one end of resistor R1, and the emitter is connected to the drain of FET Q3. The base of transistor Q2 is connected to the cathode of diode D1 and one end of resistor R3, the collector is connected to the anode of diode D2 and one end of resistor R4, and the emitter is connected to the drain of FET Q4. The gate of FET Q3 is connected to the gate of FET Q4. The source of FET Q3 receives a forward flipping control signal; the source of FET Q4 receives a reverse flipping control signal. The other ends of resistors R1, R2, R3, and R4 are grounded.

[0018] Specifically, it also includes a trigger U2, an operational amplifier U3, and a capacitor C1. The first and fourth pins of the trigger U2 and one end of resistor R8 are connected to the power supply; the second pin is connected to the sixth pin and one end of resistor R10; the third pin is connected to the output terminal of operational amplifier U3, the cathode of diode D9, and one end of resistor R9; and the fifth pin is connected to the anode of diode D8. The non-inverting input of operational amplifier U3 is connected to one end of capacitor C1, the cathodes of diodes D3 and D4, and one end of resistor R6; the inverting input is connected to one end of resistor R7 and the other end of resistor R8. The anode of diode D3 is connected to the anode of diode D2; the anode of diode D4 is connected to the anode of diode D1; the cathode of diode D8 is connected to the gate of field-effect transistor Q3; the anode of diode D9 receives the flip-over completion signal; and the other ends of resistors R6, R7, R9, R10, and C1 are grounded.

[0019] Specifically, it also includes several operational amplifiers, capacitor C2, and resistor R5. Among the several operational amplifiers, the non-inverting input of operational amplifier U1 is connected to the cathodes of diodes D5 and D6, one end of capacitor C2, and one end of resistor R5, and its output is connected to the anode of diode D7; the non-inverting input of operational amplifier U4 is connected to the inverting input of operational amplifier U5, and its output is connected to the anode of diode D6; the non-inverting input of operational amplifier U4 and the inverting input of operational amplifier U5 acquire the gas source pressure signal; the output of operational amplifier U5 is connected to the anode of diode D5; the cathode of diode D7 is connected to the cathode of diode D8; the other end of capacitor C2 and the other end of resistor R5 are grounded.

[0020] Specifically, one end of resistor R15 is connected to the inverting input of operational amplifier U4, one end of resistor R16, and the other end is connected to the non-inverting input of operational amplifier U5 and one end of resistor R14; the other end of resistor R16 is connected to the power supply; and the other end of resistor R14 is grounded.

[0021] Specifically, one end of resistor R12 is connected to the power supply, and the other end is connected to the inverting input of operational amplifier U1 and one end of resistor R11; the other end of resistor R11 is grounded.

[0022] Specifically, it also includes a resistor R13, one end of which is connected to the gate of the field-effect transistor Q3, and the other end is grounded.

[0023] Specifically, the resistor R7 is an adjustable resistor.

[0024] Specifically, resistors R14 and R15 are adjustable resistors.

[0025] Specifically, the resistor R11 is an adjustable resistor.

[0026] See appendix Figure 1The flip-board control signal is fed back by the MCU / personnel. IN_1 and IN_2 are inputs for positive and negative flip-board control signals, respectively. When the MCU feeds back a positive flip-board control signal, the signal passes through the source and drain of MOSFET Q3, the emitter and base of transistor Q1, and resistor R2 to the ground terminal. The emitter and base of transistor Q1 are forward biased, and transistor Q1 is turned on. The signal from the emitter of transistor Q1 is then collected by transistor Q1. The signal from resistor R1 is fed back to the ground terminal. When the MCU feeds back the reverse flip-board control signal, this signal passes through the source and drain of MOSFET Q4, the emitter and base of transistor Q2, and resistor R3 to the ground terminal. The emitter and base of transistor Q2 are forward biased, and transistor Q2 is turned on. The signal from the emitter of transistor Q2 passes through the collector of transistor Q2 and resistor R4 to the ground terminal. The signal at resistor R4... Feedback is sent to the solenoid valve, which contains a positive and a negative coil. When either coil is briefly energized, the solenoid valve core switches to the corresponding position, the cylinder moves accordingly, and the circuit board flips. The signals at resistors R1 and R4 are the coil energizing signals. When the solenoid valve receives the signal from resistor R1, the positive coil is energized; when it receives the signal from resistor R4, the negative coil is energized. When the circuit receives a positive flip control signal, the signal from resistor R1 is synchronously fed back to the base of transistor Q2 via diode D1, preventing transistor Q2 from conducting. When the circuit receives a negative flip control signal, the signal from resistor R4 is synchronously fed back to the base of transistor Q1 via diode D2, preventing transistor Q1 from conducting. This ensures that the solenoid valve can only receive one energizing signal, preventing damage to the valve core caused by simultaneous positive and negative flip control signals from the MCU / personnel.

[0027] The power signal passes through resistors R8 and R7 to the ground terminal. The signal amplitude at resistor R7 is the required energizing time for the coil. The required energizing time is set by adjusting the resistance value of R7 according to the solenoid valve model. The signal at resistor R7 is fed back to the inverting input of operational amplifier U3, and the signal at capacitor C1 is fed back to the non-inverting input of operational amplifier U3. Simultaneously, the signal at resistor R1 is fed back to the solenoid valve, causing the potential at capacitor C1 to rise via diode D4. Simultaneously, the signal at resistor R4 is fed back to the solenoid valve, causing the potential at capacitor C1 to rise via diode D3. When the potential at capacitor C1 rises and reaches a high level... When the signal amplitude at resistor R7 is at a certain value, one of the coils inside the solenoid valve has received the required energization time. The solenoid valve core completes the corresponding switching, the cylinder begins its extension / retraction movement, the circuit board begins to flip, and simultaneously, operational amplifier U3 outputs. The signal at the output of operational amplifier U3 is fed back to pin 3 of trigger U2. Pin 5 of trigger U2 outputs a high level. The signal at pin 5 of trigger U2 is fed back to the gates of field-effect transistors Q3 and Q4 after passing through diode D8. The voltage difference between the gate and source of field-effect transistor Q3 is higher than the conduction threshold, and field-effect transistor Q3 is turned off. When the voltage difference between the gate and source of MOSFET Q4 exceeds the turn-on threshold, MOSFET Q4 is turned off. The turn-off of MOSFETs Q3 and Q4 limits the circuit from receiving any flip-board control signal fed back by the MCU / user. Simultaneously, the signal at capacitor C1 is routed to ground via resistor R6, causing the potential at capacitor C1 to drop. When the potential at capacitor C1 drops below the signal at resistor R7, operational amplifier U3 is turned off. Resistor R13 is the parasitic capacitance discharge resistor for the gates of MOSFETs Q3 and Q4. Resistor R9 is the pull-down resistor for pin 3 of trigger U2. 0 represents the pull-down resistors at pins 2 and 6 of trigger U2. IN_3 is the input for the flip-over completion signal, which is fed back by the MCU / personnel after the flip-over is completed on the circuit board. The flip-over completion signal is fed back to pin 3 of trigger U2 via diode D9, resetting trigger U2 to its initial state. Pin 5 of trigger U2 is low, and MOSFETs Q3 and Q4 are turned on. This allows the circuit to obtain feedback of any flip-over control signal before the circuit board completes the flip-over, and removes the restriction after the flip-over is completed, preventing false flip-over caused by the forward / reverse coils being energized again if the flip-over is not complete.

[0028] The upper limit signal of the gas source pressure standard is input to the inverting input of op-amp U4, and the lower limit signal is input to the non-inverting input of op-amp U5. The upper and lower limit signals of the gas source pressure standard range can be fed back from the power supply signal. IN_4 inputs the current gas source pressure signal, which is fed back from the gas pressure sensor. The power supply signal passes through resistors R16, R15, and R14 to the ground terminal. The signal at resistor R15 is fed back to the inverting input of op-amp U4, and the signal at resistor R14 is fed back to the non-inverting input of op-amp U5. Adjusting the resistance values ​​of resistors R14 and R15 sets the upper and lower limit signals of the gas source pressure standard. When the pressure fluctuates and exceeds the upper limit of the pressure standard, operational amplifier U4 outputs. The signal from the output of operational amplifier U4 goes to ground via diode D6 and resistor R5, causing the potential of capacitor C2 to rise. When the gas source pressure fluctuates and falls below the lower limit of the pressure standard, operational amplifier U5 outputs. The signal from the output of operational amplifier U5 goes to ground via diode D5 and resistor R5, causing the potential of capacitor C2 to rise. The signal at the end of capacitor C2 is fed back to the non-inverting input of operational amplifier U1. The inverting input of operational amplifier U1 receives a reference signal, which can be fed back from the power supply signal. The power supply signal goes to ground via resistors R12 and R11, and the signal at the end of resistor R11 is the reference signal. The reference signal amplitude is set by adjusting the resistance value of resistor R11. The signal at resistor R11 is fed back to the inverting input of operational amplifier U1. When the gas source pressure fluctuates outside the standard range and causes the potential at capacitor C2 to rise above the reference signal amplitude, operational amplifier U1 outputs. The signal at the output of operational amplifier U1 is fed back to the gates of MOSFETs Q3 and Q4 via diode D7, causing MOSFETs Q3 and Q4 to be cut off. When the gas source pressure stabilizes within the standard range, the signal at capacitor C2 is fed to ground via resistor R5, causing the potential at capacitor C2 to drop. When the potential at capacitor C2 drops and falls below the reference amplitude... When the signal amplitude is at its maximum, operational amplifier U1 is cut off, and field-effect transistors Q3 and Q4 are turned on. By adjusting the reference signal amplitude, the required stabilization time for the air source pressure to enter the standard range after fluctuation can be adjusted. The lower the reference signal amplitude, the longer the required stabilization time. This limits the circuit's acquisition of the flap control signal when the air source pressure fluctuates to prevent the cylinder from moving and causing motion deviation. After the time for the air source pressure to enter the pressure standard range exceeds the required stabilization time, the restriction on the acquisition of the flap control signal is lifted to reduce the cylinder's movement during instantaneous fluctuations in air source pressure.

[0029] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No markings in the claims should be construed as limiting the scope of the claims.

Claims

1. A pneumatic control circuit for a circuit board flipping machine, characterized in that, The system includes several transistors, several diodes, several field-effect transistors (FETs), and several resistors. Transistor Q1 has its base connected to the cathode of diode D2 and one end of resistor R2, its collector connected to the anode of diode D1 and one end of resistor R1, and its emitter connected to the drain of FET Q3. Transistor Q2 has its base connected to the cathode of diode D1 and one end of resistor R3, its collector connected to the anode of diode D2 and one end of resistor R4, and its emitter connected to the drain of FET Q4. The gate of FET Q3 is connected to the gate of FET Q4. The source of FET Q3 receives a forward flip-flop control signal, and the source of FET Q4 receives a reverse flip-flop control signal. The other ends of resistors R1, R2, R3, and R4 are grounded. The system also includes a trigger U2, an operational amplifier U3, and a capacitor C.

1. The first and fourth pins of the trigger U2, and one end of resistor R8 are connected to the power supply; the second pin is connected to the sixth pin and one end of resistor R10; the third pin is connected to the output terminal of operational amplifier U3, the cathode of diode D9, and one end of resistor R9; and the fifth pin is connected to the anode of diode D8. The non-inverting input of operational amplifier U3 is connected to one end of capacitor C1, the cathodes of diodes D3 and D4, and one end of resistor R6; the inverting input is connected to one end of resistor R7 and the other end of resistor R8. The anode of diode D3 is connected to the anode of diode D2; the anode of diode D4 is connected to the anode of diode D1; the cathode of diode D8 is connected to the gate of field-effect transistor Q3; the anode of diode D9 receives the flip-over completion signal; and the other ends of resistors R6, R7, R9, R10, and C1 are grounded.

2. The pneumatic control circuit for the circuit board flipping machine according to claim 1, characterized in that, It also includes several operational amplifiers, capacitor C2, and resistor R5. Among the several operational amplifiers, the non-inverting input of operational amplifier U1 is connected to the cathodes of diodes D5 and D6, one end of capacitor C2, and one end of resistor R5, and the output is connected to the anode of diode D7; the non-inverting input of operational amplifier U4 is connected to the inverting input of operational amplifier U5, and the output is connected to the anode of diode D6; the non-inverting input of operational amplifier U4 and the inverting input of operational amplifier U5 acquire the gas source pressure signal; the output of operational amplifier U5 is connected to the anode of diode D5; the cathode of diode D7 is connected to the cathode of diode D8; the other end of capacitor C2 and the other end of resistor R5 are grounded.

3. The pneumatic control circuit for the circuit board flipping machine according to claim 2, characterized in that, Of the resistors, one end of resistor R15 is connected to the inverting input of operational amplifier U4, one end of resistor R16, and the other end is connected to the non-inverting input of operational amplifier U5 and one end of resistor R14; the other end of resistor R16 is connected to the power supply; and the other end of resistor R14 is grounded.

4. The pneumatic control circuit for the circuit board flipping machine according to claim 2, characterized in that, One end of resistor R12 is connected to the power supply, and the other end is connected to the inverting input of operational amplifier U1 and one end of resistor R11; the other end of resistor R11 is grounded.

5. The pneumatic control circuit for the circuit board flipping machine according to claim 1, characterized in that, It also includes a resistor R13, one end of which is connected to the gate of the field-effect transistor Q3, and the other end is grounded.

6. The pneumatic control circuit for the circuit board flipping machine according to claim 1, characterized in that, The resistor R7 is an adjustable resistor.

7. The pneumatic control circuit for the circuit board flipping machine according to claim 3, characterized in that, The resistors R14 and R15 are adjustable resistors.

8. The pneumatic control circuit for the circuit board flipping machine according to claim 4, characterized in that, The resistor R11 is an adjustable resistor.

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