A voltage regulating sampling circuit suitable for split-type gas shielded welding machine

Abstract

The utility model discloses a kind of voltage regulating sampling circuit suitable for split gas shielded welding machine include: host end circuit and wire feeder end circuit;Host end circuit provides power supply VCC to wire feeder end circuit, and carries out the sampling of regulating voltage;Wire feeder end circuit include: regulating potentiometer, sawtooth wave voltage generating circuit and comparison circuit;The input end of regulating potentiometer is connected with power supply VCC, the ground end of regulating potentiometer is grounded, for by changing resistance value, output adjusted voltage;Sawtooth wave voltage generating circuit is connected with power supply VCC, for output sawtooth wave voltage;Comparison circuit is connected with the output end of regulating potentiometer, sawtooth wave voltage generating circuit, for adjusted voltage and sawtooth wave voltage, comparison circuit is connected with host end circuit.The utility model whole circuit design structure is simple, cost is lower, and when sampling detection, voltage loss generated on connecting line will not be influenced, the result of measurement is more accurate.

Description

Technical Field

[0001] This utility model relates to the field of gas shielded welding machine circuit technology, and in particular to a voltage regulation sampling circuit suitable for split gas shielded welding machines. Background Technology

[0002] CO2 gas shielded welding machines, commonly used in inverter welding, typically employ a split structure in industrial models. This means the inverter power supply (main unit) is one part, and the wire feeder is another. To enable long-distance use, the control cable connecting the two can be as long as 50 meters. For ease of use, the control knob is usually located on the wire feeder for convenient adjustment by the welder.

[0003] The knobs on wire feeders typically use rotary potentiometers, connected to the main unit via cables. The main unit's circuitry performs AD sampling. If the control cables are long, significant losses can occur in the wiring harness. The voltage sampled by the main unit may not be accurate, leading to discrepancies between the main unit's parameters and the user's preset values ​​when adjusting the wire feeder. A common industry solution is to digitize the wire feeder's control by adding a microcontroller to the wire feeder, sampling locally and transmitting the data to the main unit via digital communication. While this method effectively solves the problem, it is costly and requires extensive experience in digitization to implement. Summary of the Invention

[0004] According to an embodiment of the present invention, a voltage regulation sampling circuit suitable for a split-type gas shielded welding machine is provided, comprising: a main unit end circuit and a wire feeder end circuit; The main unit circuit provides power VCC to the wire feeder circuit and samples the voltage for regulation. The wire feeder end circuit includes: an adjustment potentiometer, a sawtooth wave voltage generation circuit, and a comparison circuit; The input terminal of the potentiometer is connected to the power supply VCC, and the ground terminal of the potentiometer is grounded. It is used to output the adjusted voltage by changing the resistance value. The sawtooth wave voltage generation circuit is connected to the power supply VCC and is used to output sawtooth wave voltage. The comparator circuit is connected to the output of the potentiometer and the sawtooth wave voltage generation circuit. It is used to compare the voltage adjusted by the potentiometer with the sawtooth wave voltage output by the sawtooth wave voltage generation circuit. The comparator circuit is also connected to the host circuit.

[0005] Furthermore, the sawtooth wave production circuit includes: a first resistor, a second resistor, a third resistor, a transistor, a first capacitor, a first comparator, a fourth resistor, a fifth resistor, a sixth resistor, a first MOSFET, a seventh resistor, and a second MOSFET; One end of the first resistor and the third resistor are connected to the power supply VCC; One end of the second resistor is connected to the other end of the first resistor and the base of the transistor, while the other end of the second resistor is grounded. The emitter of the transistor is connected to the other end of the third resistor; One end of the first capacitor is connected to the collector of the transistor, the comparator circuit, the drain of the first MOSFET, and the non-inverting input of the first comparator; the other end of the first capacitor is grounded. One end of the fourth resistor is connected to the power supply VCC, and the other end of the fourth resistor is connected to one end of the fifth resistor, one end of the sixth resistor, and the inverting input of the first comparator. The other end of the fifth resistor is connected to the source of the second MOSFET and then grounded; The other end of the sixth resistor is connected to the drain of the second MOSFET; The output of the first comparator is connected to one end of the seventh resistor, the gate of the second MOSFET, and the gate of the first MOSFET. The other end of the seventh resistor is connected to the power supply VCC; The source of the first MOSFET is grounded.

[0006] Furthermore, the comparator circuit includes: a second comparator and an eighth resistor; The non-inverting input of the second comparator is connected to the output of the adjusting potentiometer, the inverting input of the second comparator is connected to the sawtooth wave voltage generation circuit, and the output of the second comparator is connected to the host circuit and one end of the eighth resistor. The other end of the eighth resistor is connected to the power supply VCC.

[0007] Furthermore, the comparator circuit is connected to the host circuit via a connecting wire.

[0008] Furthermore, it also includes a second capacitor, one end of which is connected to the output terminal of the adjustment potentiometer, and the other end is grounded.

[0009] Furthermore, the host-side circuitry includes: a ninth resistor, a tenth resistor, and an MCU; One end of the ninth resistor is connected to the comparator circuit, and the other end of the ninth resistor is connected to one end of the tenth resistor and the MCU. The other end of the tenth resistor is grounded.

[0010] According to an embodiment of the present invention, an adjustable voltage sampling circuit suitable for a split gas shielded welding machine has a simple overall circuit design and low cost. Furthermore, during sampling and detection, it is not affected by voltage loss generated on the connection line, resulting in more accurate measurement results.

[0011] It should be understood that both the foregoing general description and the following detailed description are exemplary and intended to provide further illustration of the claimed technology. Attached Figure Description

[0012] Figure 1 This is a circuit diagram of a voltage adjustment sampling circuit suitable for a split-type gas shielded welding machine according to an embodiment of the present invention. Detailed Implementation

[0013] The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings, further illustrating the present invention.

[0014] First, combine Figure 1 This invention describes a voltage regulation sampling circuit suitable for a split-type gas shielded welding machine, according to an embodiment of the present invention. It is used for regulating voltage sampling and has a wide range of applications.

[0015] like Figure 1 As shown, an embodiment of the present invention provides a voltage regulation sampling circuit suitable for a split-type gas shielded welding machine, which has a main unit end circuit and a wire feeder end circuit. Specifically, such as Figure 1 As shown, the host circuit provides power VCC and GND to the wire feeder circuit and samples the voltage for adjustment.

[0016] Specifically, such as Figure 1 As shown, the wire feeder end circuit includes: an adjusting potentiometer VR1, a sawtooth wave voltage generation circuit, and a comparator circuit; the input terminal of the adjusting potentiometer VR1 is connected to the power supply VCC, and the ground terminal of the adjusting potentiometer VR1 is grounded, used to output the adjusted voltage by changing the resistance value; the sawtooth wave voltage generation circuit is connected to the power supply VCC, used to output the sawtooth wave voltage; the comparator circuit is connected to the output terminal of the adjusting potentiometer VR1 and the sawtooth wave voltage generation circuit, used to compare the voltage adjusted by the adjusting potentiometer VR1 with the sawtooth wave voltage output by the sawtooth wave voltage generation circuit, and the comparator circuit is connected to the main unit end circuit.

[0017] Furthermore, such as Figure 1As shown, the sawtooth wave generation circuit includes: a first resistor R1, a second resistor R2, a third resistor R3, a transistor Q1, a first capacitor C1, a first comparator U1A, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a first MOSFET T1, a seventh resistor R7, and a second MOSFET T2; one end of the first resistor R1 and the third resistor R3 are connected to the power supply VCC; one end of the second resistor R2 is connected to the other end of the first resistor R1 and the base of the transistor Q1, and the other end of the second resistor R2 is grounded; the emitter of the transistor Q1 is connected to the other end of the third resistor R3; one end of the first capacitor C1 is connected to the collector of the transistor Q1, the comparator circuit, and the drain of the first MOSFET T1. The non-inverting input of the first comparator U1A is connected, and the other end of the first capacitor C1 is grounded; one end of the fourth resistor R4 is connected to the power supply VCC, and the other end of the fourth resistor R4 is connected to one end of the fifth resistor R5, one end of the sixth resistor R6, and the inverting input of the first comparator U1A; the other end of the fifth resistor R5 is connected to the source of the second MOSFET T2 and then grounded; the other end of the sixth resistor R6 is connected to the drain of the second MOSFET T2; the output of the first comparator U1A is connected to one end of the seventh resistor R7, the gate of the second MOSFET T2, and the gate of the first MOSFET T1; the other end of the seventh resistor R7 is connected to the power supply VCC; the source of the first MOSFET T1 is grounded.

[0018] Furthermore, such as Figure 1 As shown, the comparator circuit includes: a second comparator U1B and an eighth resistor R8; the non-inverting input of the second comparator U1B is connected to the output of the adjusting potentiometer VR1, the inverting input of the second comparator U1B is connected to the sawtooth wave voltage generation circuit, the output of the second comparator U1B is connected to the host circuit and one end of the eighth resistor R8; the other end of the eighth resistor R8 is connected to the power supply VCC.

[0019] Furthermore, such as Figure 1 As shown, the comparator circuit is connected to the host circuit via a connecting wire.

[0020] Furthermore, such as Figure 1 As shown, an embodiment of the present invention provides a voltage regulation sampling circuit suitable for a split gas shielded welding machine, which further includes a second capacitor C2. One end of the second capacitor C2 is connected to the output terminal of the regulating potentiometer VR1, and the other end is grounded. The second capacitor C2 is used for filtering.

[0021] Furthermore, such as Figure 1 As shown, the host circuit includes: a ninth resistor R9, a tenth resistor R10, and an MCU; one end of the ninth resistor R9 is connected to the comparator circuit, and the other end of the ninth resistor R9 is connected to one end of the tenth resistor R10 and the MCU; the other end of the tenth resistor R10 is grounded.

[0022] Working principle: When the power is first applied, the first resistor R1 and the second resistor R2 divide the voltage of the power supply VCC. The emitter E of the transistor Q1 is connected to the power supply VCC through the third resistor R3. At this time, the base B voltage of the transistor Q1 is less than the emitter E voltage, so the transistor Q1 is turned on and begins to charge the first capacitor C1. At this time, the voltage at the non-inverting input terminal of the first comparator U1A increases from zero. The voltage at the inverting input terminal is divided by the fourth resistor R4 and the fifth resistor R5, so the voltage at the non-inverting input terminal is less than that at the inverting input terminal. The output pin of the first comparator U1A is connected to the seventh resistor R7, which is pulled up to the power supply VCC. It outputs a low level in open-drain mode, and both the first MOSFET T1 and the second MOSFET T2 are turned off. When the voltage across the first capacitor C1 rises above the voltage at the inverting input, the first comparator U1A outputs a high level, and the first MOSFET T1 and the second MOSFET T2 simultaneously turn on. Since the second MOSFET T2 is on, the sixth resistor R6 is relatively small, so the voltage at the inverting input of the first comparator U1A is close to 0V at this time. Because the first MOSFET T1 is turned on, the voltage on the first capacitor C1 discharges through the first MOSFET. When the voltage drops to 0V, the non-inverting input of the first comparator U1A is lower than the inverting input, so it outputs a low level. The first MOSFET T1 and the second MOSFET T2 are turned off. Therefore, the first capacitor C1 is repeatedly charged and discharged. The charging is through the third resistor R3, so it is relatively slow. The discharging is through the first MOSFET T1 directly to GND, so it is relatively fast, forming a sawtooth wave. The voltage across the first resistor R1 is simultaneously connected to the inverting input of the second comparator U1B. The output of the adjustment potentiometer VR1, which is actually adjusted on the wire feeder, is filtered by the second capacitor C2 and then connected to the non-inverting input of the second comparator U1B. The output of the second comparator U1B is also connected to the eighth pull-up resistor R8. When the voltage Vin output by the potentiometer VR1 is greater than the sawtooth wave voltage, the second comparator U1B outputs a high level. When the voltage Vin output by the potentiometer VR1 is less than the sawtooth wave voltage, the second comparator U1B outputs a low level. Since the waveform of the sawtooth wave is fixed, when Vin changes linearly, a PWM waveform with a similarly linearly changing duty cycle will be output. This PWM waveform reaches the host through the connecting line, and after being divided by the ninth resistor R9 and the tenth resistor R10, it enters the microcontroller. The microcontroller can detect the duty cycle of this waveform and calculate the Vin voltage.

[0023] The above solution transforms the voltage AD sampling signal into a measurement duty cycle value. Even if voltage loss occurs on the connection line, it does not affect the measurement result, making the measurement more accurate.

[0024] It should be noted that, in this specification, the terms "comprising," "including," or any other variations thereof are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0025] Although the present invention has been described in detail through the preferred embodiments above, it should be understood that the above description should not be considered as a limitation of the present invention. Various modifications and substitutions to the present invention will be apparent to those skilled in the art after reading the above content. Therefore, the scope of protection of the present invention should be defined by the appended claims.

Claims

1. A voltage regulation sampling circuit suitable for a split-type gas shielded welding machine, characterized in that, Includes: main unit circuitry and wire feeder circuitry; The host circuit provides power VCC to the wire feeder circuit and samples the voltage for adjustment. The wire feeder end circuit includes: an adjustment potentiometer, a sawtooth wave voltage generation circuit, and a comparison circuit. The input terminal of the adjustment potentiometer is connected to the power supply VCC, and the ground terminal of the adjustment potentiometer is grounded, which is used to output the adjusted voltage by changing the resistance value; The sawtooth wave voltage generation circuit is connected to the power supply VCC and is used to output sawtooth wave voltage. The comparison circuit is connected to the output terminal of the adjustment potentiometer and the sawtooth wave voltage generation circuit, and is used to compare the voltage adjusted by the adjustment potentiometer with the sawtooth wave voltage output by the sawtooth wave voltage generation circuit. The comparison circuit is connected to the host terminal circuit.

2. The voltage regulation sampling circuit for a split-type gas shielded welding machine as described in claim 1, characterized in that, The sawtooth wave production circuit includes: a first resistor, a second resistor, a third resistor, a transistor, a first capacitor, a first comparator, a fourth resistor, a fifth resistor, a sixth resistor, a first MOSFET, a seventh resistor, and a second MOSFET; One end of the first resistor and one end of the third resistor are connected to the power supply VCC; One end of the second resistor is connected to the other end of the first resistor and the base of the transistor, and the other end of the second resistor is grounded; The emitter of the transistor is connected to the other end of the third resistor; One end of the first capacitor is connected to the collector of the transistor, the comparator circuit, the drain of the first MOS transistor, and the non-inverting input of the first comparator; the other end of the first capacitor is grounded. One end of the fourth resistor is connected to the power supply VCC, and the other end of the fourth resistor is connected to one end of the fifth resistor, one end of the sixth resistor, and the inverting input terminal of the first comparator. The other end of the fifth resistor is connected to the source of the second MOS transistor and then grounded; The other end of the sixth resistor is connected to the drain of the second MOS transistor; The output terminal of the first comparator is connected to one end of the seventh resistor, the gate of the second MOS transistor, and the gate of the first MOS transistor. The other end of the seventh resistor is connected to the power supply VCC. The source of the first MOSFET is grounded.

3. The voltage adjustment sampling circuit for a split-type gas shielded welding machine as described in claim 1, characterized in that, The comparison circuit includes: a second comparator and an eighth resistor; The non-inverting input of the second comparator is connected to the output of the adjusting potentiometer, the inverting input of the second comparator is connected to the sawtooth wave voltage generation circuit, and the output of the second comparator is connected to the host circuit and one end of the eighth resistor. The other end of the eighth resistor is connected to the power supply VCC.

4. The voltage adjustment sampling circuit for a split-type gas shielded welding machine as described in claim 1, characterized in that, The comparison circuit is connected to the host circuit via a connecting line.

5. The voltage adjustment sampling circuit for a split-type gas shielded welding machine as described in claim 1, characterized in that, It also includes: a second capacitor, one end of which is connected to the output terminal of the adjustment potentiometer, and the other end is grounded.

6. The voltage regulation sampling circuit for a split-type gas shielded welding machine as described in claim 1, characterized in that, The host-side circuit includes: a ninth resistor, a tenth resistor, and an MCU; One end of the ninth resistor is connected to the comparator circuit, and the other end of the ninth resistor is connected to one end of the tenth resistor and the MCU; The other end of the tenth resistor is grounded.

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