CN115255582A - Inverter type direct-current plasma double-air-valve cutting machine and control circuit - Google Patents
Inverter type direct-current plasma double-air-valve cutting machine and control circuit Download PDFInfo
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- CN115255582A CN115255582A CN202210919731.0A CN202210919731A CN115255582A CN 115255582 A CN115255582 A CN 115255582A CN 202210919731 A CN202210919731 A CN 202210919731A CN 115255582 A CN115255582 A CN 115255582A
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- 238000005520 cutting process Methods 0.000 title claims abstract description 84
- 238000001514 detection method Methods 0.000 claims abstract description 110
- 238000002955 isolation Methods 0.000 claims description 29
- 230000000087 stabilizing effect Effects 0.000 claims description 14
- 238000010891 electric arc Methods 0.000 claims description 11
- NIOPZPCMRQGZCE-WEVVVXLNSA-N 2,4-dinitro-6-(octan-2-yl)phenyl (E)-but-2-enoate Chemical compound CCCCCCC(C)C1=CC([N+]([O-])=O)=CC([N+]([O-])=O)=C1OC(=O)\C=C\C NIOPZPCMRQGZCE-WEVVVXLNSA-N 0.000 claims description 3
- 238000012423 maintenance Methods 0.000 abstract description 2
- 239000003990 capacitor Substances 0.000 description 21
- 238000010586 diagram Methods 0.000 description 5
- 235000014676 Phragmites communis Nutrition 0.000 description 4
- 230000002093 peripheral effect Effects 0.000 description 4
- 230000009977 dual effect Effects 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
- 238000007664 blowing Methods 0.000 description 2
- 230000008878 coupling Effects 0.000 description 2
- 238000010168 coupling process Methods 0.000 description 2
- 238000005859 coupling reaction Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 238000003466 welding Methods 0.000 description 2
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K10/00—Welding or cutting by means of a plasma
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K10/00—Welding or cutting by means of a plasma
- B23K10/006—Control circuits therefor
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Abstract
The invention discloses an inversion type direct-current plasma double-air-valve cutting machine and a control circuit, wherein the double-air-valve cutting machine comprises an air source, a main air valve, an auxiliary air valve and a double-air-valve control circuit, one end of the main air valve is connected with the air source, the other end of the main air valve is connected with a main air path and an auxiliary air path, the main air path is directly used for conveying air to the cutting machine, the auxiliary air path is provided with the auxiliary air valve, the size of the air flow conveyed to the cutting machine is controlled by the auxiliary air valve, and the double-air-valve control circuit is respectively connected with the main air valve and the auxiliary air valve and is used for controlling the main air valve and the auxiliary air valve to act; the control circuit comprises a main loop current detection circuit, an output detection control circuit, a main air valve control circuit, an auxiliary air valve control circuit and a no-load detection control circuit; according to a gun switching signal, a no-load signal and a main loop current signal, the opening or the closing of a main air valve and an auxiliary air valve are controlled, so that the arc continuity is high when the arc maintenance function is ensured, and the arc breaking phenomenon is avoided; avoid damaging the nozzle and the electrode of the cutting torch and improve the success rate of arc striking.
Description
Technical Field
The invention relates to the technical field of cutting machine control, in particular to an inverter type direct-current plasma double-air valve cutting machine and a control circuit.
Background
Cutting, generally referred to as cutting of metal. The working principle of the direct current plasma cutting machine is as follows: the cutting method is that the local metal is melted rapidly by the superfine and high-temperature plasma arc, and then the melted metal is blown away by airflow.
At present, a conventional inversion type direct current plasma double-gas valve cutting machine only has one gas valve, a gas valve control circuit only needs to control the single gas valve, the cutting machine has a compressed gas flow in both the arc maintaining function and the cutting function, the problems of arc interruption and small electric arc often occur in the control, and meanwhile, in the arc maintaining and cutting process, the arc striking success rate is low; the plasma arc is smaller, so that the electrode loss of the cutting gun nozzle is increased, and the use cost is increased.
Therefore, it is an urgent problem to control the gas in different states of the cutting machine.
Disclosure of Invention
The invention aims to provide an inverter type direct-current plasma double-air-valve cutting machine and a control circuit, which are used for detecting the current of a main circuit, opening a main air valve and an auxiliary air valve in a pilot arc state, supplying matched small-flow gas to a pilot arc, ensuring strong arc continuity in the pilot arc function and avoiding arc breaking; under the cutting state, the main air valve and the auxiliary air valve are controlled to be switched, the nozzle and the electrode of the cutting gun are prevented from being damaged due to the fact that plasma arcs are discontinuous or small, and the arc striking success rate is improved.
In a first aspect, the above object of the present invention is achieved by the following technical solutions:
the utility model provides an inverter type direct current plasma double-air valve cutting machine, includes air supply, main air valve, vice pneumatic valve, double-air valve control circuit, and main air valve one end is connected with the air supply, and main gas circuit, vice pneumatic circuit are connected to the other end, and wherein main gas circuit directly is used for the cutting machine conveying gas, sets up vice pneumatic valve on the vice pneumatic circuit, and the air current size of carrying on the cutting machine is controlled through vice pneumatic valve, and double-air valve control circuit is connected with main air valve, vice pneumatic valve respectively for control main air valve, vice pneumatic valve action.
The invention is further configured to: the double-air valve control circuit detects the current of the main loop, judges the circuit state and controls the opening or closing of the double-air valve, in the cutting state, the current of the main loop flows back to the negative pole of the power supply from the positive pole of the power supply through the workpiece and the electrode, the electric arc is established between the electrode and the workpiece, and the main air valve is opened; under the state of pilot arc, the output of the inverter flows back to the negative pole of the power supply from the positive pole through the no-load circuit, the nozzle and the electrode, the electric arc is established between the electrode and the nozzle, the main air valve and the auxiliary air valve are opened at the same time, and the auxiliary air valve is used for shunting the gas in the gas pipe; under the no-load state, the no-load current is detected, the main air valve is closed, the auxiliary air valve is opened, and the air in the air pipe is discharged.
The invention is further configured to: when a gunhand switch of the cutting machine is pressed, the double-air valve control circuit detects that the main loop has voltage output, controls the main air circuit to supply air, pulls an electric arc between the electrode and the nozzle, and controls the auxiliary air valve to attract and shunt the air flow of the cutting machine after pulling; when the cutting gun is close to a workpiece, the small arc is converted into a large arc, the double-air valve control circuit detects that current exists in the main loop, the auxiliary air valve is closed, and air exhaust is stopped; when a gunhand switch of the cutting machine is released, the inverter does not work, the main air valve is still in a conducting state, and the electrode and the nozzle are in a disconnecting state; and the cutting machine pistol switch is pressed again, the inverter works, the double-air valve control circuit detects no-load signals, the main air valve is controlled to be closed, the auxiliary air valve is controlled to be opened, residual air in the air pipe is discharged, and the electrode and the nozzle are accelerated to reset.
In a second aspect, the above object of the present invention is achieved by the following technical solutions:
a control circuit of an inverter type direct current plasma double-air valve cutting machine comprises a main loop current detection circuit, an output detection control circuit, a main air valve control circuit and an auxiliary air valve control circuit; the output detection control circuit is respectively connected with the main air valve control circuit and the auxiliary air valve control circuit and is used for outputting a third signal S3 to the auxiliary air valve control circuit and outputting a fourth signal S4 to the main air valve control circuit according to the magnitude of the output voltage; the main air valve control circuit is used for controlling the on-off state of the main air valve according to the cutter gun on-off signal S and the fourth signal S4; the main loop current detection circuit is connected with the auxiliary air valve control circuit, and outputs a fifth signal S5 to the auxiliary air valve control circuit according to whether current flows through the main loop; and the auxiliary air valve control circuit is used for controlling the opening and closing states of the auxiliary air valve according to the cutting machine gun opening and closing signal S, the third signal S3 and the fifth signal S5.
The invention is further configured to: the no-load detection control circuit is respectively connected with the main loop current detection circuit and the output detection control circuit and is used for detecting whether the main loop is in an no-load state or not, outputting a first signal S1 to the main loop current detection circuit and outputting a second signal S2 to the output detection control circuit according to a detection result; the main loop current detection circuit is used for outputting a fifth signal S5 to the auxiliary air valve control circuit according to whether current flows through the main loop and the first signal S1; the output detection control circuit is used for outputting a third signal S3 to the auxiliary air valve control circuit and outputting a fourth signal S4 to the main air valve control circuit according to the magnitude of the output voltage and the second signal S2.
The invention is further configured to: the output detection control circuit comprises a voltage control circuit, a first isolation circuit, a first inverter circuit and a first switch circuit which are sequentially connected, wherein the voltage control circuit controls whether the first isolation circuit is isolated and conducted according to the magnitude of output voltage and the magnitude of a second signal S2, the first isolation circuit is used for isolating an output power supply and a control power supply, the first inverter circuit inverts the output signal of the first isolation circuit to control the switching state of the first switch circuit, the first switch circuit outputs a third signal S3 to an auxiliary air valve control circuit, and a fourth signal S4 to a main air valve control circuit.
The invention is further configured to: the no-load detection control circuit comprises a no-load voltage detection circuit, a voltage stabilizing circuit, a second isolating circuit and a second inverter circuit which are connected in sequence; the voltage stabilizing circuit is used for stabilizing the no-load voltage or the output voltage to provide a voltage signal conforming to the second isolating circuit, the second isolating circuit is used for isolating the output power supply from the control power supply, and the second inverter circuit outputs the first signal S1.
The invention is further configured to: the main air valve control circuit comprises a delay circuit and a second switch circuit which are sequentially connected, and after a gun switch of the cutting machine is pressed down, the second switch circuit is controlled to be switched on or switched off by the aid of the delay circuit alone or in combination with a fourth signal.
The invention is further configured to: the main loop current detection circuit comprises a magnetic current detection element and two unidirectional current elements, one end of the first unidirectional current element is connected with the output of the no-load detection control circuit, the other end of the first unidirectional current element is connected with one end of the magnetic current detection element, and the other end of the magnetic current detection element is connected with a power ground; one end of the second one-way current element is connected with the output of the no-load detection control circuit, and the other end of the second one-way current element is connected with the output end of a fifth signal S5 of the output detection control circuit; when the magnetic current detection element detects that current flows through the main loop, the main loop current detection circuit outputs low level; when the magnetic current detection element detects that no current flows in the main loop, the output of the main loop current detection circuit is the same as the first signal.
The invention is further configured to: the auxiliary air valve control circuit comprises an auxiliary air valve first control circuit and an auxiliary air valve second control circuit which are mutually connected; the second control circuit of the auxiliary air valve outputs a sixth signal S6 to the first control circuit of the auxiliary air valve according to the third signal S3 and the fifth signal S5; the first control circuit of the auxiliary air valve is used for controlling the on-off state of the auxiliary air valve according to the cutting machine gun on-off signal S and the sixth signal S6.
Compared with the prior art, the beneficial technical effect of this application does:
1. the double-gas and control circuit is arranged to detect the current of the main loop, control the magnitude of the gas flow according to the current state of the main loop, ensure the arc interruption, and improve the success rate of arc striking;
2. further, the current detection coil is arranged in the main loop, and when current is detected, the large air flow is controlled, so that cutting blowing is guaranteed; when no current exists, small air flow is controlled to ensure arc maintenance;
3. further, the control circuit of this application, according to main loop current, output voltage, rifle on-off state, the opening or closing of control main air valve, vice pneumatic valve realizes the control of air current when the cutting machine is different states, improves the cutting machine effect, reduce cost.
Drawings
FIG. 1 is a schematic view of a gas path structure of a dual gas valve cutting machine according to an embodiment of the present application;
FIG. 2 is a schematic view of the air flow direction of a dual air valve cutting machine according to an embodiment of the present application;
FIG. 3 is a block diagram representation of a control circuit according to an embodiment of the present application;
FIG. 4 is a schematic diagram of an output detection control circuit according to an embodiment of the present application;
FIG. 5 is a schematic diagram of an empty load detection control circuit according to an embodiment of the present application;
FIG. 6 is a schematic diagram of a main gas valve control circuit according to an embodiment of the present application;
fig. 7 is a schematic diagram of a control circuit according to an embodiment of the present application.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings.
The utility model provides an inverter type direct current plasma double air valve cutting machine gas circuit structure, as shown in figure 1, including air supply, relief pressure valve, main air valve, vice pneumatic valve, double air valve control circuit, air supply, relief pressure valve, main air valve, vice pneumatic valve connect gradually, and double air valve control circuit is connected with main air valve, vice pneumatic valve respectively for opening or shutting down of control main air valve, vice pneumatic valve.
The main gas circuit and the auxiliary gas circuit come out from the main gas valve, wherein the main gas circuit is directly used for conveying gas to the cutting machine, the auxiliary gas circuit is provided with the auxiliary gas valve, and the size of the gas flow conveyed to the cutting machine is controlled through the auxiliary gas valve.
When a gun switch of the cutting machine is pressed down, a high-level signal is output, the double-air-valve control circuit detects that voltage output exists in the main loop, the main air valve is controlled to be opened, an electric arc between an electrode and a nozzle of the cutting machine is pulled up, at the moment, the double-air-valve control circuit detects current between the electrode and the nozzle, the auxiliary air valve is opened, and air flow of the cutting machine is shunted.
When the cutting gun is close to a workpiece, the small arc is converted into a large arc, the double-air valve control circuit detects that current flows in the main loop, and controls the auxiliary air valve to be disconnected to stop exhausting.
When the hand switch is released, the inverter does not work, the welding machine has no output, the main gas valve is in an opening state, the electrode and the nozzle are in a disconnecting state, the hand switch is pressed down again, the inverter works, the double-gas valve control circuit detects a no-load voltage signal, the main gas valve is closed, the auxiliary gas valve is opened, residual gas in the gas pipe is exhausted, and the electrode and the nozzle are accelerated to reset.
The utility model provides an inverter type direct current plasma double air valve cutting machine circuit structure, as shown in figure 2, inverter type direct current circuit's transformer T secondary current changes the direct current into through full-bridge rectifier circuit, and current sensor detects inverter circuit and whether has the current flow.
When current flows in the main loop, the coil L1 generates a magnetic field, the main loop current detection circuit detects that current flows in the main loop, the current in the main loop flows back to the negative electrode of the power supply from the positive electrode of the power supply through the workpiece and the electrode, and an electric arc is established between the electrode and the workpiece. The control circuit judges the circuit state by collecting the switching signal of the current detection device and controls the double air valves to be opened or closed.
Under the pilot arc state, the main loop current detection circuit detects that no current flows through the main loop, the no-load detection control circuit detects that the current flows through the no-load detection control circuit, the inverter circuit outputs the current which flows back to the negative pole of the power supply from the positive pole of the power supply through the no-load detection control circuit, the nozzle and the electrode, and the electric arc is established between the electrode and the nozzle.
The control circuit of the inverter type direct-current plasma double-air-valve cutting machine comprises a no-load detection control circuit, a main loop current detection circuit, an output detection control circuit, a main air valve control circuit and an auxiliary air valve control circuit, as shown in fig. 3.
The auxiliary air valve control circuit comprises an auxiliary air valve first control circuit and an auxiliary air valve second control circuit which are mutually connected.
The no-load detection control circuit is respectively connected with the main loop current detection circuit and the output detection control circuit and is used for detecting whether the main loop is in a no-load state or not, outputting a first signal S1 to the main loop current detection circuit and outputting a second signal S2 to the output detection control circuit according to a detection result.
The output detection control circuit is respectively connected with the no-load detection control circuit, the main air valve control circuit and the auxiliary air valve second control circuit, and outputs a third signal S3 to the auxiliary air valve second control circuit and a fourth signal S4 to the main air valve control circuit according to the magnitude of the output voltage.
The main air valve control circuit controls the opening and closing state of the main air valve according to the cutter gun switching signal S and the fourth signal S4.
The main loop current detection circuit is respectively connected with the no-load detection control circuit and the auxiliary air valve second control circuit, and the main loop current detection circuit outputs a fifth signal S5 to the auxiliary air valve second control circuit according to whether current flows through the main loop or not and the first signal S1.
And the second control circuit of the auxiliary air valve outputs a sixth signal S6 to the first control circuit of the auxiliary air valve according to the third signal S3 and the fifth signal S5.
And the auxiliary air valve controls the opening and closing state of the auxiliary air valve according to the cutting machine gun opening and closing signal S and the sixth signal S6.
The output detection control circuit, as shown in fig. 4, includes a voltage control circuit, a first isolation circuit, a first inverter circuit, and a first switch circuit, which are connected in sequence, where the voltage control circuit outputs a first signal S11 to the first isolation circuit according to the magnitude of the output voltage and the magnitude of the second signal S2, the first isolation circuit is used for isolating the output power supply from the control power supply, the first inverter circuit inverts a first second signal S12 output by the first isolation circuit, outputs a first third signal S13 to control the on-off state of the first switch circuit, and the first switch circuit outputs a third signal S3 to the second control circuit of the secondary air valve and a fourth signal S4 to the main air valve control circuit.
The output voltage is a voltage between the terminals CP3 and CP 5.
The voltage control circuit is conducted when the voltage is larger than a set value and is not conducted when the voltage is smaller than or equal to the set value.
The first isolation circuit includes a photoelectric isolation element. The first inverter circuit includes an inverter device. The first switching circuit includes a triode switching circuit.
The no-load detection control circuit, as shown in fig. 5, includes a no-load voltage detection circuit, a voltage stabilizing circuit, a second isolation circuit, and a second inverter circuit, which are connected in sequence.
The no-load voltage detection circuit comprises a no-load detection resistor and is used for collecting no-load voltage.
The voltage stabilizing circuit is used for stabilizing the no-load voltage or the output voltage to provide a voltage signal S21 conforming to a second isolating circuit, the second isolating circuit is used for isolating the output power supply and the control power supply and outputting a second signal S22 to a second inverter circuit, and the second inverter circuit outputs a first signal S1.
The no-load voltage is determined by the input at the A/B terminal.
The main air valve control circuit, as shown in fig. 6, includes a delay circuit and a second switch circuit connected in sequence, and the main air valve controller employs a relay.
When the switch of the cutting machine gun is switched on, the delay circuit delays for a set time and outputs a third signal S31 to the second switch circuit for controlling the action of the main air valve relay.
The first control circuit of the auxiliary air valve comprises a third switch circuit which is used for outputting a sixth signal S6 according to the switching signal of the cutting machine gun.
The second control circuit of the auxiliary air valve comprises a fourth switch circuit which is used for controlling the action of an auxiliary air valve relay according to a third signal S3, a sixth signal S6 and a fifth signal.
The main loop current detection circuit comprises a magnetic current detection element and two one-way current elements, wherein in a specific embodiment of the application, the magnetic current detection element adopts a reed switch.
One end of the first one-way current element is connected with the output of the no-load detection control circuit, the other end of the first one-way current element is connected with one end of the magnetic current detection element, and the other end of the magnetic current detection element is connected with the power ground.
One end of the second one-way current element is connected with the output of the no-load detection control circuit, and the other end of the second one-way current element is connected with the output end of a fifth signal S5 of the output detection control circuit.
When the magnetic current detection element detects that current flows in the main loop, two ends of the magnetic current detection element are connected, and the main loop current detection circuit outputs low level.
When the magnetic current detection element detects that no current flows in the main loop, the output of the main loop current detection circuit is the same as the first signal.
In one embodiment of the present application, a control circuit of an inverter type dc plasma dual gas valve cutting machine is shown in fig. 7.
The voltage-controlled circuit comprises a voltage-controlled resistor RV1, when the output voltage is higher than the set voltage value or the no-load voltage is higher than the set voltage value, the voltage-controlled resistor RV1 is conducted, otherwise, the voltage-controlled resistor RV is not conducted.
The first isolation circuit comprises a photoelectric isolation element U5, wherein the positive end of the input side of the photoelectric isolation element U5 is connected with the output of the voltage-controlled circuit through a resistor R44, a diode D29 and a capacitor C21 are connected between the positive end and the negative end of the input side in parallel, and the negative end of the diode D29 is connected with the positive end of the input side.
The positive end of the output side of the photoelectric isolation element U5 is connected with a control circuit power supply VDD through a resistor R38; the output side negative terminal is connected to the input terminal of the first inverter circuit via a resistor R40 and to the control power supply ground via a resistor R39.
A diode D22 is connected in parallel at two ends of the resistor R40, and the positive end of the diode D22 is connected with the input end of the first inverter circuit.
The input end of the first inverting circuit is connected with the control power ground through a capacitor C15.
The first inverting circuit includes an inverter U3F having a schmitt trigger function.
The first switch circuit comprises an NPN triode switch circuit, and the base of an NPN triode Q1 is connected to the output of the first inverter circuit through a resistor R19, the control power ground through a resistor R2 and the control power ground through a capacitor C4.
The resistor R19 and the resistor R2 divide the voltage of the output of the first inverter circuit to obtain the base voltage of the NPN triode Q1.
The emitter of the NPN triode Q1 is connected with the ground of the control power supply, the collector of the NPN triode Q1 is connected with the fourth signal S4 end of the main gas valve control circuit, and a third signal S3 is output to the secondary gas valve second control circuit through the series combination of the diode D15 and the resistor R15. The positive terminal of the diode D15 is connected to the collector.
The no-load detection resistor is a 1 ohm resistor.
The voltage stabilizing circuit comprises a voltage stabilizing tube D28, wherein the negative electrode of the voltage stabilizing tube D28 is connected with one end and a voltage output end of the no-load detection circuit, the positive electrode of the voltage stabilizing tube D28 is connected with the first input end of the second isolating circuit, and the second input end of the second isolating circuit is connected with the other end of the no-load detection circuit. After the no-load voltage or the output voltage passes through the voltage stabilizing circuit, the no-load voltage or the output voltage is applied to two input ends of the second isolating circuit.
The second isolation circuit comprises a photoelectric isolation element U4 and a peripheral circuit thereof, a first input end of an input side of the photoelectric isolation element U4 is used as a first input end of the second isolation circuit and is connected with an anode of a voltage regulator tube D28, a cathode of a diode D27 and one end of a capacitor C20, a second input end of the input side is connected with an anode of the diode D27, the other end of the capacitor C20 and one end of a resistor R43, and the other end of the resistor R43 is used as a second input end of the second isolation circuit.
The input end of the output side of the photoelectric isolation element U4 is connected with the input end of the second inverter circuit, one end of the resistor R37 and one end of the capacitor C16, the other end of the resistor R37 is connected with the control power supply VDD, and the output end of the output side of the resistor R37 and the other end of the capacitor C16 are connected with the control power supply ground.
The second inverter circuit comprises an inverter U3E with a Schmitt trigger function and a resistor R31, wherein the input of the inverter U3E is connected with the input end of the output side of the photoelectric isolation circuit, the output of the inverter U3E is connected with one end of the resistor R31, and the other end of the resistor R31 is used as the output end of the second inverter circuit.
The main loop current detection circuit comprises a diode D26, a diode D21, a magnetic current sensing element, a resistor R42 and a capacitor C17. The resistor R42 and the capacitor C17 are connected in series and then connected in parallel with two ends of the magnetic current sensing element, and the anode of the diode D26 and the anode of the diode D21 are connected together and are simultaneously connected with the output end of the second inverter circuit; the cathode of the diode D26 is connected with one end C of the magnetic current sensing element, and the other end D of the magnetic current sensing element is connected with the control power ground; and the cathode of the diode D21 is used as the output end of the main loop current detection circuit and is connected with the input end of the secondary air valve second control circuit.
In one embodiment of the present application, the magnetic current sensing element is a reed switch, and the reed switch is activated when current flows through the main circuit, and is deactivated when current does not flow through the main circuit.
When the second inverter circuit outputs a low level, the output of the main loop current detection circuit is at a low level regardless of whether current flows through the main loop; when the second inverter circuit outputs a high level, the output of the main circuit current detection circuit is at a high level when a current flows through the main circuit, and the output of the main circuit current detection circuit is at a low level when the current does not flow through the main circuit.
In the main air valve control circuit, the time delay circuit comprises a diode D5 and a capacitor C5, the anode of the diode D5 is connected to the output end of a cutting machine gun switching signal, the cathode of the diode D5 is connected with one end of the capacitor C5, one end of a resistor R3, one end of the capacitor C3 and the control electrode of the power tube Q2, and the other end of the capacitor C5, the other end of the resistor R3 and the other end of the capacitor C3 are connected with a control power ground.
The second switch circuit comprises a power tube Q2 and a peripheral circuit thereof, the input end of the power tube Q2 is connected with one end of the main air valve control element, the other end of the main air valve control element is connected with a power supply VSS, the output end of the power tube Q2 is connected with a fourth signal S4 end of the output detection control circuit and one end of a resistor R1, and the other end of the resistor R1 is connected with the power supply VSS.
In one particular embodiment of the present application, the main gas valve control element is relay JD1A.
The high level of cutter rifle switching signal charges for electric capacity C5 through diode D5, and when charging certain voltage, power tube Q2 switches on, detects the output voltage of control circuit's first output according to the output, decides whether relay JD1A switches on the actuation.
The first control circuit of the auxiliary air valve comprises a power tube Q6 and a peripheral circuit thereof, the anode of a diode D6 is connected with the output end of a switching signal of a cutting machine gun, the cathode of the diode D6 is connected with one end of a resistor R6 and the control electrode of the power tube Q6, and the other end 6 of the resistor R6 is connected with a control power ground.
The input end of the power tube Q6 is connected with one end of the auxiliary air valve control element, the other end of the auxiliary air valve control element is connected with the power supply VSS, and the output end of the power tube Q6 is connected with the sixth signal S6 end of the first control circuit of the auxiliary air valve.
And the secondary air valve second control circuit comprises an NPN triode Q7 and a peripheral circuit thereof. The base electrode of the triode Q7 is connected with one end of the resistor R17, one end of the resistor R5 and one end of the capacitor C8, the other end of the resistor R17 is connected with the output end of a third signal S3 of the output detection control circuit and the output end of a fifth signal S5 of the main loop current detection circuit, the other end of the resistor R5, the other end of the capacitor C8 and the emitting electrode of the triode Q7 are connected with a control power ground, and the collecting electrode of the triode Q7 outputs a sixth signal S6 to the first control circuit of the auxiliary air valve.
When the Q1 is conducted, the fourth signal S4 is at a low level, if the cutting machine gun is closed, the switching signal S is at a high level, the power tube Q2 is conducted through the time delay of the capacitor C5, the main air valve is pulled in and opened, the main air valve supplies air, at the moment, the Q7 is cut off, the auxiliary air valve does not act, and the cutting machine gun is in a closed state.
On the contrary, when Q1 is turned off, the fourth signal S4 is at a high level, and if the cutter gun is turned off, the switching signal S is at a high level, and after the delay of the capacitor C5, the power tube Q2 is turned off, the main gas valve is not operated, and at this time, Q7 is turned on, the sub-gas valve is operated, and gas is supplied.
The implementation principle of the embodiment is as follows:
when the gun switch of the cutting machine is pressed, the control part sends a control signal, the inverter works, the main loop has voltage output, and current is generated between the electrode and the nozzle (the gun structure is characterized in that the electrode and the nozzle are in a short circuit state under the state of no current). Meanwhile, a gun switching signal S generates a high-level signal of 11.5V, so that a control electrode of a power tube Q6 is at a high potential, the high-level signal charges a capacitor C5 through a diode D5, when the charging potential of the capacitor C5 reaches 2.5V, at the moment, because the electrode and a nozzle are in a short-circuit state, the voltage between output voltage ends CP3 and CP5 is very low and cannot break down a voltage-controlled resistor RV1, a light coupling U5 of a first isolation circuit does not emit light, the input end of an inverter U3F is at a low potential, the output end of the inverter U3F is at a high potential (VDD), a triode Q1 in the output control circuit is conducted, a power tube Q2 in a main air valve control circuit is conducted, a main air valve relay JD1A is closed, a main air circuit is opened for air supply, a cutter electrode moves backwards under the action of air flow, and an electric arc between the electrode and the nozzle is pulled up.
After being pulled up, the current of 15-20A flows through a no-load resistor of 1R, and the no-load voltage U of the A/B end AB The voltage is 15-20V, the optical coupler U4 of the second isolation circuit emits light, the output of the phase inverter U3E is high potential (VDD), the triode Q7 in the second control circuit of the auxiliary air valve is conducted, and the relay JD2A of the auxiliary air valve conducts in an attraction mode to shunt the airflow of the cutting machine gun.
When the cutting gun is close to a workpiece, the small arc is changed into a large arc, the reed switch is closed, the detection end C, D in the main loop current detection circuit is switched on, a signal with 0 potential difference is generated, the anode of the diode D26 is pulled down to 0.7V, correspondingly, the cathode of the diode Q21 is also 0 potential, Q7 is cut off, the auxiliary air valve JD2A is switched off, and exhaust is stopped.
The output voltage terminals CP3, CP5 function to detect signals: when the cutting machine is in a back blowing state, namely a gunner switch of the cutting machine is released, the inverter does not work, the welding machine does not output, but charges stored in a capacitor C5 exist, a power tube Q2 in a main air valve control circuit is still in a conducting state, a main air valve is in a conducting state, an electrode and a nozzle are in a disconnecting state, the gunner switch of the cutting machine is pressed again, the inverter works, a 350V no-load voltage signal is detected between output voltage ends CP3 and CP5, a voltage-controlled resistor RV1 is broken down, a light coupling U5 in a first isolating circuit emits light, a first phase inverter U3F outputs a low potential (0V), a triode Q1 in a first switching circuit is cut off, the main air valve is closed, meanwhile, a power supply VSS (+ 24V) provides a high level for a base electrode Q7 in a second control circuit of an auxiliary air valve through a resistor JD1, a diode D15, a resistor R15 and a resistor R17 branch circuit, the auxiliary air valve is turned on, residual air in an air pipe is discharged, and the electrode and the nozzle is reset. Thereafter, the next pilot arc process is started.
The embodiments of the present invention are preferred embodiments of the present invention, and the scope of the present invention is not limited by these embodiments, so: all equivalent changes made according to the structure, shape and principle of the invention are covered by the protection scope of the invention.
Claims (10)
1. The utility model provides an inverter type direct current plasma double-air valve cutting machine, its characterized in that includes air supply, main air valve, vice pneumatic valve, double-air valve control circuit, and main air valve one end is connected with the air supply, and the main gas circuit, vice pneumatic circuit are connected to the other end, and wherein the main gas circuit directly is used for the cutting machine air feed, sets up vice pneumatic valve on the vice pneumatic circuit, and the air current size of carrying on the cutting machine is controlled through vice pneumatic valve, and double-air valve control circuit is connected with main air valve, vice pneumatic valve respectively for control main air valve, vice pneumatic valve action.
2. The inverter type direct-current plasma dual-air valve cutting machine according to claim 1, wherein the dual-air valve control circuit detects a main loop current, judges a circuit state, controls the opening or closing of the dual-air valve, and in the cutting state, the current of the main loop flows back to a power supply cathode from a power supply anode through a workpiece and an electrode, an electric arc is established between the electrode and the workpiece, and the main air valve is opened; under the state of pilot arc, the output of the inverter flows back to the cathode of the power supply from the anode through the no-load circuit, the nozzle and the electrode, the arc is established between the electrode and the nozzle, the main air valve and the auxiliary air valve are opened simultaneously, and the auxiliary air valve is used for shunting the gas in the gas pipe; under the no-load state, the no-load current is detected, the main air valve is closed, the auxiliary air valve is opened, and the air in the air pipe is discharged.
3. The inverter type direct-current plasma double-air-valve cutting machine according to claim 1, wherein when a gunner switch of the cutting machine is pressed, the double-air-valve control circuit detects that the main loop has voltage output, the main air circuit is controlled to supply air, an electric arc between an electrode and a nozzle is pulled up, and after the electric arc is pulled up, the double-air-valve control circuit controls the auxiliary air valve to be closed, and the air flow of the cutting machine is shunted; when the cutting gun is close to a workpiece, the small arc is converted into a large arc, the double-air valve control circuit detects that current exists in the main loop, the auxiliary air valve is closed, and air exhaust is stopped; when a gun hand switch of the cutting machine is released, the inverter does not work, the main air valve is still in a conducting state, and the electrode and the nozzle are in a disconnecting state; and the gun switch of the cutting machine is pressed again, the inverter works, the double-air-valve control circuit detects a no-load signal, the main air valve is controlled to be closed, the auxiliary air valve is controlled to be opened, residual air in the air pipe is discharged, and the resetting of the electrode and the nozzle is accelerated.
4. A control circuit of an inverter type direct current plasma double-air valve cutting machine is characterized by comprising a main loop current detection circuit, an output detection control circuit, a main air valve control circuit and an auxiliary air valve control circuit; the output detection control circuit is respectively connected with the main air valve control circuit and the auxiliary air valve control circuit and is used for outputting a third signal S3 to the auxiliary air valve control circuit and outputting a fourth signal S4 to the main air valve control circuit according to the magnitude of the output voltage; the main air valve control circuit is used for controlling the on-off state of the main air valve according to the cutter gun on-off signal S and the fourth signal S4; the main loop current detection circuit is connected with the auxiliary air valve control circuit, and outputs a fifth signal S5 to the auxiliary air valve control circuit according to whether current flows through the main loop; and the auxiliary air valve control circuit is used for controlling the opening and closing states of the auxiliary air valve according to the cutting machine gun opening and closing signal S, the third signal S3 and the fifth signal S5.
5. The inverter type direct-current plasma double-air valve cutting machine control circuit according to claim 4, characterized by further comprising an idle load detection control circuit, wherein the idle load detection control circuit is respectively connected with the main loop current detection circuit and the output detection control circuit, and is used for detecting whether the main loop is in an idle load state, outputting a first signal S1 to the main loop current detection circuit and outputting a second signal S2 to the output detection control circuit according to a detection result; the main loop current detection circuit is used for outputting a fifth signal S5 to the auxiliary air valve control circuit according to whether current flows through the main loop and the first signal S1; the output detection control circuit is used for outputting a third signal S3 to the auxiliary air valve control circuit and outputting a fourth signal S4 to the main air valve control circuit according to the magnitude of the output voltage and the second signal S2.
6. The control circuit of the inverter type direct-current plasma dual-air valve cutting machine according to claim 5, wherein the output detection control circuit comprises a voltage control circuit, a first isolation circuit, a first inverter circuit and a first switch circuit which are connected in sequence, the voltage control circuit controls whether the first isolation circuit is isolated and conducted or not according to the magnitude of the output voltage and the magnitude of the second signal S2, the first isolation circuit is used for isolating the output power supply from the control power supply, the first inverter circuit inverts the output signal of the first isolation circuit to control the on-off state of the first switch circuit, and the first switch circuit outputs a third signal S3 to the auxiliary air valve control circuit and a fourth signal S4 to the main air valve control circuit.
7. The inverter type direct-current plasma double-air valve cutting machine control circuit according to claim 5, wherein the no-load detection control circuit comprises a no-load voltage detection circuit, a voltage stabilizing circuit, a second isolation circuit and a second inverter circuit which are connected in sequence; the voltage stabilizing circuit is used for stabilizing the no-load voltage or the output voltage to provide a voltage signal conforming to the second isolating circuit, the second isolating circuit is used for isolating the output power supply from the control power supply, and the second inverter circuit outputs the first signal S1.
8. The control circuit of the inverter type direct-current plasma double-air valve cutting machine according to claim 4, wherein the main air valve control circuit comprises a delay circuit and a second switch circuit which are sequentially connected, and after a gun switch of the cutting machine is pressed down, the second switch circuit is controlled to be switched on or switched off through delay of the delay circuit alone or in combination with a fourth signal.
9. The inverter type direct-current plasma double-air valve cutting machine control circuit according to claim 4, wherein the main loop current detection circuit comprises a magnetic current detection element and two unidirectional current elements, one end of the first unidirectional current element is connected with the output of the no-load detection control circuit, the other end of the first unidirectional current element is connected with one end of the magnetic current detection element, and the other end of the magnetic current detection element is connected with a power ground; one end of the second one-way current element is connected with the output of the no-load detection control circuit, and the other end of the second one-way current element is connected with the output end of a fifth signal S5 of the output detection control circuit; when the magnetic current detection element detects that current flows through the main loop, the main loop current detection circuit outputs low level; when the magnetic current detection element detects that no current flows in the main loop, the output of the main loop current detection circuit is the same as the first signal.
10. The inverter type direct-current plasma double-air valve cutting machine control circuit according to claim 4, wherein the auxiliary air valve control circuit comprises an auxiliary air valve first control circuit and an auxiliary air valve second control circuit which are connected with each other; the second control circuit of the auxiliary air valve outputs a sixth signal S6 to the first control circuit of the auxiliary air valve according to the third signal S3 and the fifth signal S5; the first control circuit of the auxiliary air valve is used for controlling the on-off state of the auxiliary air valve according to the cutting machine gun on-off signal S and the sixth signal S6.
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| CN202210919731.0A CN115255582B (en) | 2022-08-02 | 2022-08-02 | Inverter type direct-current plasma double-air-valve cutting machine and control circuit |
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Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20030141286A1 (en) * | 2002-01-30 | 2003-07-31 | Komatsu Industries Corp. | Main arc ignition device and main arc ignition control method of plasma cutting machine |
| CN101985187A (en) * | 2010-09-19 | 2011-03-16 | 深圳市华意隆实业发展有限公司 | Energy storage inverter type air plasma cutter for rescue emergencies |
| CN202097491U (en) * | 2011-05-26 | 2012-01-04 | 昆山瑞凌焊接科技有限公司 | Plasma cutting pilot arc circuit |
| CN202780200U (en) * | 2012-07-26 | 2013-03-13 | 湖南超宇科技有限公司 | Digital machine plasma cutter |
| CN207563896U (en) * | 2017-10-10 | 2018-07-03 | 深圳市普耐尔科技有限公司 | A kind of non-high frequency plasma cutting machine arc-maintaining device |
| CN207824152U (en) * | 2018-01-09 | 2018-09-07 | 吴忠市黄河电焊机有限公司 | A kind of double air valve plasma digital control cutting machines |
| CN111872532A (en) * | 2020-08-20 | 2020-11-03 | 深圳市佳士科技股份有限公司 | Cutting machine control device and low-frequency arc striking plasma cutting machine |
| CN212599592U (en) * | 2020-06-04 | 2021-02-26 | 杭州凯尔达电焊机有限公司 | Arc striking device of plasma cutting equipment |
-
2022
- 2022-08-02 CN CN202210919731.0A patent/CN115255582B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20030141286A1 (en) * | 2002-01-30 | 2003-07-31 | Komatsu Industries Corp. | Main arc ignition device and main arc ignition control method of plasma cutting machine |
| CN101985187A (en) * | 2010-09-19 | 2011-03-16 | 深圳市华意隆实业发展有限公司 | Energy storage inverter type air plasma cutter for rescue emergencies |
| CN202097491U (en) * | 2011-05-26 | 2012-01-04 | 昆山瑞凌焊接科技有限公司 | Plasma cutting pilot arc circuit |
| CN202780200U (en) * | 2012-07-26 | 2013-03-13 | 湖南超宇科技有限公司 | Digital machine plasma cutter |
| CN207563896U (en) * | 2017-10-10 | 2018-07-03 | 深圳市普耐尔科技有限公司 | A kind of non-high frequency plasma cutting machine arc-maintaining device |
| CN207824152U (en) * | 2018-01-09 | 2018-09-07 | 吴忠市黄河电焊机有限公司 | A kind of double air valve plasma digital control cutting machines |
| CN212599592U (en) * | 2020-06-04 | 2021-02-26 | 杭州凯尔达电焊机有限公司 | Arc striking device of plasma cutting equipment |
| CN111872532A (en) * | 2020-08-20 | 2020-11-03 | 深圳市佳士科技股份有限公司 | Cutting machine control device and low-frequency arc striking plasma cutting machine |
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