KR100900757B1 - Apparatus for automatic changing power of electrical welding machine - Google Patents

Abstract

An automatic power change device of an electric welding machine is provided to prevent electric shock accident by omitting power source change work of the electric welding machine. An automatic power change device of an electric welding machine comprises a variable control unit(100) consisting of a relay controller(110), a trans controller(120) and a power controller(130). The relay controller connects a first contact point of the relay in case input voltage is lower than reference voltage and connects a second contact point of the relay in case the input voltage is greater than the reference voltage by comparing the input voltage with the reference voltage. The trans controller connects first and second trans coils of a high frequency converter to be parallel in case the first contact point of the relay is connected and connects first and second trans coils to be serial in case the second contact point of the relay is connected. The power controller connects the first contact point of the relay for the power source selection to use inverter driving voltage as first driving voltage in case the first contact point of the relay is connected and connects the second contact point of the relay for the power source selection to use the inverter driving voltage as second driving voltage in case the second contact point of the relay is connected.

Description

Automatic power converter of electric welding machine {APPARATUS FOR AUTOMATIC CHANGING POWER OF ELECTRICAL WELDING MACHINE}

The present invention relates to an automatic power converter of an electric welder, and more particularly, to an automatic power converter of an electric welder which can be converted and used automatically according to the power supply voltage input in the field without user setting. will be.

There are many types of electric welding machines, and one of them is a welding machine using an inverter that converts a commercial alternating current from a converter to a direct current, an inverter generates a high frequency alternating current, and then converts it back to a direct current.

The input power of the electric welding machine using the inverter mainly uses 220V, 380V, 440V, and is configured to convert the power through the power converter of the inverter according to the input power of the site.

1 to 3 are diagrams illustrating power conversion circuits and voltage settings of a conventional electric welding machine.

A conventional inverter power supply for an electric welding machine includes a full-wave rectifier circuit (2) for converting a three-phase AC power source (1) into a direct current, and a first smoothing capacitor for smoothing the ripple voltage included in the direct current ( 6a) and the second smoothing capacitor 6b and the first and second smoothing capacitors 6a and 6b respectively receive operating voltages and are operated alternately in response to the application of the control signal to generate high frequency output voltages. A first terminal drawn from a connection point between the first high frequency conversion circuit 3 and the second high frequency conversion circuit 4 to be applied to the transformer, and the output of the full wave rectifying circuit 2 and the input of the first smoothing capacitor 6a; Second terminal 25 drawn from the connection point between the other output of the full-wave rectifying circuit 2 and the input of the second smoothing capacitor 6b, and the first and second smoothing capacitors 6a and 6b. The third and fourth terminals 23 and 26 drawn out from the type force of the adjacent Extending to one point, the first smoothing capacitor 6a and the first high frequency conversion circuit 3 and the second smoothing capacitor 6b and the second high frequency conversion circuit 4 correspond to the input power supply. It consists of a power conversion terminal box (7) interconnected in series or in parallel between the outputs.

The wiring of the power conversion terminal box 7 is connected to the first terminal 22 and the third terminal 23 as shown in FIG. 2 when 220V is input as the input power source 1, and the second terminal. By connecting the busbars 30 so that the 25 and the fourth terminals 26 are connected, the first and second smoothing capacitors 6a and 6b are connected in parallel, and the first and second high frequency conversion circuits ( 3 and 4) are also connected in parallel.

On the other hand, when 440V is input as an input power supply, for example, as shown in FIG. 3, the first and second terminals 23 and 4 are connected to each other by the same bus bar 30, thereby providing the first and second terminals. The smoothing capacitors 6a and 6b are connected in series, and the first and second high frequency conversion circuits 3 and 4 are also connected in series so that the DC voltage divided by the smoothing capacitors 6a and 6b is divided into the first and the second. 2 is applied to the high frequency conversion circuits 3 and 4, respectively.

 However, the power conversion terminal box 7 of the conventional electric welding machine has to disconnect the copper busbar 30 fixed through the bolt or the like from each terminal when the input voltage is changed, and newly connect and fix it according to the input power. There is a problem.

In addition, when a power is input between the user connecting the busbars 30 according to the input power, there is a problem that a dangerous accident occurs in which the user is electrocuted.

In addition, the power conversion terminal box 7 is configured to be exposed to the outside of the main body of the electric welder to change the input power, there is a problem that a short circuit accident of the exposed terminal occurs.

In addition, when a power larger than the input power set by the user is input to the electric welder, the electric welder is damaged due to excessive input power, and when a power smaller than the input power set by the user is input, the welding function is not provided because the preset accurate output is not provided. There is a problem that can not be performed.

In order to solve the above problems, an object of the present invention is to provide an automatic power conversion apparatus of an electric welder that can be used to automatically convert the power of the inverter according to the power supply voltage input in the field without user setting.

In order to achieve the above object, the present invention includes a capacitor for smoothing the ripple voltage of the direct current converted by rectifying the input voltage, and the first and second transformer coils are connected to both ends of the capacitor to generate a high frequency output voltage. A power conversion device of an electric welding machine having a high frequency conversion unit, wherein the high frequency conversion unit is provided such that a primary side of a first transformer coil and a primary side of a second transformer coil are connected in series or in parallel according to an input voltage. In accordance with the characterized in that it comprises a variable control unit for varying the number of windings of the primary side of the transformer coil.

The variable controller compares the input voltage with a preset reference voltage to connect the first contact of the relay if the input voltage is less than the reference voltage, and connect the second contact of the relay if the input voltage is greater than the reference voltage. A relay control unit; When the first contact point of the relay is connected, the first and second transformer coils of the high frequency converter are connected in parallel. When the second contact point of the relay is connected, the first and second transformer coils are connected in series. A transformer control unit to enable; And when the first contact of the relay is connected, connects the first contact of the power selection relay so that the inverter driving voltage becomes the first driving voltage, and when the second contact of the relay is connected, the inverter driving voltage is second. And a power control unit for connecting the second contact of the power selection relay to be a driving voltage.

The relay controller may include a transformer including a primary coil having at least two first and second winding numbers and a secondary coil corresponding to the primary coil; One side of the first contact point and the second contact point are respectively connected to an input power source, the other side of the first contact point is connected to the first winding of the transformer, and the other side of the second contact point is connected to the second winding point of the transformer. relay; A first contact point is connected to a secondary coil corresponding to the first winding of the transformer, and the second contact point is connected to a secondary coil corresponding to the second winding of the transformer; And comparing the input voltage with a preset reference voltage and outputting a low signal such that the first contact of the input and output relay is connected when the input voltage is less than the reference voltage, and outputting the low signal when the input voltage is greater than or equal to the reference voltage. And a power detector for outputting a high signal such that the second contact of the output relay is connected.

In addition, the transformer control unit is connected to the point where the start of the primary winding of the first transformer coil and the start of the primary winding of the second transformer coil is connected, the end point of the end of the primary winding of the first transformer coil, A relay for parallel connection to connect an end point at which the primary winding of the second transformer coil is terminated; And a relay for series connection such that a point at which the primary winding of the first transformer coil starts and an end point at which the primary winding of the second transformer coil ends are connected to each other.

The power control unit may include a transformer including a primary coil having at least two first and second winding numbers and a secondary coil corresponding to the primary coil; And one side of the first contact point and the second contact point respectively connected to an input power source, the other side of the first contact point is connected to the first winding of the transformer, and the other side of the second contact point is connected to the second winding of the transformer. And a relay for selecting a power source.

As described above, the automatic power converter of the electric welding machine according to the present invention has an advantage of performing a welding function regardless of the input power voltage.

In addition, the automatic power conversion device of the electric welder according to the present invention does not need to perform a power change operation of the electric welder according to the input voltage of the site has the advantage of preventing the risk of electric shock accident of the user.

In addition, the automatic power conversion device of the electric welder according to the present invention, the power of the inverter is automatically converted according to the input voltage to prevent breakage of the electric welder due to excessive input voltage, and to reduce the output of the electric welder due to the low input voltage There is an advantage that can be prevented.

In addition, the automatic power conversion device of the electric welding machine according to the present invention is configured to provide the same output in one high frequency conversion circuit for two input voltage, there is an advantage that can simplify the circuit with a reduction in the number of parts have.

Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings.

First, repetitive description of the same configuration as in the prior art is omitted, and the same reference numerals are used for the same configuration.

Figure 4 is a block diagram schematically showing the configuration of the automatic power conversion device of the electric welding machine according to the present invention, Figure 5 is an electrical circuit diagram showing the configuration of the relay control unit of the electric welder according to Figure 4, Figure 6 is an electrical circuit according to Figure 4 It is an electric circuit diagram which showed the structure of the transformer part of a welding machine, and FIG. 7 is an electric circuit diagram which shows the structure of the power supply part of the electric welder which concerns on FIG.

The same reference numerals are used for the same components as in the prior art, and repeated descriptions of the same components are omitted.

4 to 7, the electric welding machine according to the present invention rectifies the input power and converts the input power into direct current, and is connected to both ends of the capacitor 6 to smooth the converted ripple voltage of the direct current. It includes a variable control unit 100 for automatically converting the number of windings of the transformer coil of the high frequency converter to generate, preferably the variable control unit 100, the relay control unit 110, the transformer control unit 120 and the power control unit 130 Is made of.

When the input power of the relay control unit 110 is input to the electric welding machine, the voltage of the input power is detected and analyzed, and the driving voltage of any one of the first driving voltage and the second driving voltage preset according to the analysis result. The configuration is such that the electric welder can operate.

That is, the relay controller 110 compares the input voltage with a preset reference voltage (for example, 300 V) so that the first contact of the relay is connected when the input voltage is less than the reference voltage, and the input voltage is equal to or greater than the reference voltage. In this case, the second contact of the relay is connected.

The relay controller 110 will be described in more detail. The relay controller 110 includes a power detector 111, an input relay 112, an output relay 113, and a transformer 114.

The power detector 111 compares the input voltage with a preset reference voltage, and when the input voltage is less than the reference voltage, the first contacts c and d of the input relay 112 and the first of the output relay 113. A low signal is output so that the contacts c 'and d' are connected. When the input voltage is equal to or greater than the reference voltage, the second contact a and b of the input relay 112 and the second contact of the output relay 113 are output. Outputs a high signal so that (a ', b') is connected.

The input relay 112 is configured to have the first contacts c and d and the second contacts a and b, and for example, when a low signal is input from the power detector 111, the first contact is inputted. (c, d) are connected, and when a high signal is input, the first contacts (a, b) are connected.

In addition, the first contact point c and the second contact point a of the input relay 112 are respectively connected to an input power source, and the other side of the first contact point d is connected to a first winding of the transformer 114. The other side of the second contact (b) is connected to the second winding of the transformer 114, according to the switching operation of the input relay 112, any one of the first contact (c, d) and the second contact (a, b) Contact is connected.

The output relay 113 is configured to have first contacts c 'and d' and second contacts a 'and b', and for example, a low signal is input from the power detector 111. In this case, the first contacts c 'and d' are connected, and when a high signal is input, the first contacts a 'and b' are connected.

In addition, the first contact (c ', d') of the output relay 113 is connected to the secondary coil corresponding to the first winding of the transformer 114, the second contact (a ', b') is a transformer One of the first contacts c 'and d' and the second contact a 'and b' is connected to a secondary coil corresponding to the second winding of 114 according to a switching operation of the output relay 113. One contact is connected.

In addition, when the first contact (c ', d') of the output relay 113 is connected, the parallel connection relay 123 installed in the transformer control unit 120 is connected, the second contact (a ', b'). ) Is connected, the serial connection relay 124 installed in the transformer control unit 120 and the power selection relay 131 installed in the power control unit 130 are turned on together.

The transformer 114 is composed of a primary coil having at least two first and second windings and a secondary coil corresponding to the primary coil, the first winding being, for example, a voltage of 220V. When the voltage is supplied to the input voltage, the corresponding voltage is induced in the secondary coil, and the second winding number is, for example, when a voltage of 380 V is supplied as the input voltage, the voltage corresponding to the secondary coil is induced. .

That is, the parallel connection relay 123 and the series connection relay 124 installed in the transformer control unit 120 according to the switching state of the output unit relay 113 connected to the secondary coil of the transformer 114 and the power control unit ( The state in which the contacts of the power selection relay 131 installed in the 130 is connected is determined.

The transformer control unit 120 is connected to the first transformer coil 121 and the second transformer coil 122 in parallel when the first contact (c ', d') of the output relay 113 is connected. When the second contacts c and d of the output relay 113 are connected, the first transformer coil 121 and the second transformer coil 122 are connected in series.

To this end, the transformer control unit 120 is connected to the point (1 ') of the start of the primary winding of the first transformer coil 121 and the point (3') of the start of the primary winding of the second transformer coil 122 is connected. A plurality of parallel connections are connected such that an end point 2 'at which the primary winding of the first transformer coil 121 is terminated and an end point 4' at which the primary winding of the second transformer coil 122 is terminated are connected. The relay 123 is installed.

In addition, the transformer control unit 120 is connected so that the point (1 ') at which the primary winding of the first transformer coil 121 starts and the end point (4') at which the primary winding of the second transformer coil 122 is terminated. The relay 124 for serial connection is provided.

Therefore, when the relay 123 for parallel connection operates, the contact 'a' and the contact 'b' are connected, and the contact 'c' and the contact 'd' are connected so that the primary winding of the first transformer coil 121 is connected. The starting point 1 'is connected to the point 3' at which the primary winding of the second transformer coil 122 is started, and the end point 2 'at which the primary winding of the first transformer coil 121 is terminated. And an end point 4 'at which the primary winding of the second transformer coil 122 is terminated, and the primary side of the first transformer coil 121 and the second transformer coil 122 are connected in parallel to wind the transformer coil. Since the number is not changed, for example, a voltage corresponding to a voltage of 220 V is induced on the secondary side of the transformer coil.

In addition, when the relay 124 for serial connection is operated, the contact point 'b' and the contact point 'c' are connected to the point 1 'at which the primary winding of the first transformer coil 121 starts and the second transformer coil ( By connecting the end point 4 'at which the primary winding of 122 is terminated, the number of turns is changed. Thus, for example, even when a voltage of 380 V is input, the number of turns is changed so that the voltage induced at the secondary side of the transformer coil is constant. The voltage can be output.

When the first contacts c 'and d' of the output relay 113 are connected, the power controller 130 may select the power source selection relay 131 such that the inverter driving voltage becomes the first driving voltage (eg, 220V). When the first contact (c, d) of the () and the second contact (a ', b') of the output relay 130 is connected, the inverter drive voltage is the second drive voltage (for example, 380V) The second contacts a and b of the power source selection relay 131 are connected to each other.

To this end, the power control unit 130 is connected to the first contact point (c) and the second contact point (a), respectively, the input power, the other side (d) of the first contact point is connected to the first winding of the transformer 132 The other side (b) of the second contact point is a power source selection relay 131 connected to the second winding of the transformer 132, a primary coil having at least two first and second windings, and the primary coil. It consists of a transformer 132 made of a secondary coil corresponding to the.

Therefore, when the first contact (c ', d') of the output relay 113 is connected, the first contact (c, d) of the power selection relay 131 is connected, the output of the relay 113 When the second contacts a 'and b' are connected, the second contacts a and b of the power selection relay 131 are connected to each other so that the first driving voltage may be changed according to the connection state of the power selection relay 131. For example, the driving voltage of any one of 220V and the second driving voltage 380V is induced in the secondary coil of the transformer 132 to be applied to the inverter circuit.

The following describes the operation of the automatic power conversion device of the electric welding machine according to the present invention.

(Initial state)

The variable control unit 100 of the electric welding machine is initially set in a state in which power is not applied from the outside, and the input relay 112 and the output relay 113 of the relay control unit 110 are respectively the first contacts c and d. , c ', d' are connected, the parallel connection relay 123 of the transformer control unit 120 is connected, and the power selection relay 131 of the power control unit 130 is connected to the first contact point c. d) stays connected.

In addition, the relay 124 for series connection of the transformer 120 maintains an open state.

(When 220V is supplied by external power)

When power is applied from the outside, the variable control unit 100 of the electric welding machine compares the voltage of the applied power with a reference voltage (for example, 380V) preset in the power detector 111, and the applied power is the If it is less than the reference voltage, the power detector 111 outputs a low signal to the input relay 112 connected to the primary coil of the transformer 114 of the relay controller 110 and the secondary coil of the transformer 114 of the relay controller 110. The output relay 113 connected to is connected to the first contact (c, d, c ', d'), respectively.

Accordingly, the relay 123 for parallel connection of the transformer unit 120 connects the contact 'a' to the contact 'b' and the contact 'c' to the contact 'd' so that the first transformer coil 121 and the second are connected. The transformer coils 122 are connected in parallel.

Therefore, the number of turns of the transformer coil is not changed, so that a current corresponding to 220 V is generated in the secondary coil (not shown).

In addition, the power selection relay 131 of the power control unit 130 is not provided with the ON signal (connecting the second contact) from the output relay 113, the first contact (c, d) connected state A voltage of 220 V is applied to the primary coil of the transformer 132 of the power control unit 130 by maintaining the current, and the current generated in the secondary coil of the transformer 132 is provided to the inverter driving circuit of the electric welder.

(When 380 V is supplied from an external power source)

When power is applied from the outside, the variable control unit 100 of the electric welding machine compares the voltage of the applied power with a reference voltage (for example, 380V) preset in the power detector 111, and the applied power is If the reference voltage or more, the power detector 111 outputs a high signal to the input unit relay 112 connected to the primary coil of the transformer 114 of the relay controller 110 and the secondary coil of the transformer 114 of the relay controller 110. Output relays 113 connected to the second contacts a, b, a ', and b' are respectively connected.

Accordingly, the relay 123 for parallel connection of the transformer unit 120 is in an open state, and the relay 124 for series connection is turned on so that the contact 'b' and the contact 'c' are connected to the first transformer coil 121. And the second transformer coil 122 are connected in series.

Therefore, the number of turns of the transformer coil is increased to generate a current equal to the current generated at 220V in the secondary coil (not shown). That is, by changing the number of windings according to the input voltage, the output of the secondary side can be kept constant, so that the output value can be kept constant regardless of the input value.

In addition, the power selection relay 131 of the power control unit 130 is provided with an ON signal (connected to the second contact) from the output relay 113 so that the first contacts c and d have an open state. The second contact points a and b are connected to each other so that a voltage of 220 V is applied to the primary coil of the transformer 132 of the power control unit 130, thereby generating the secondary coil of the transformer 132. The current is provided to the inverter drive circuit of the electric welder.

Therefore, it is possible to use freely without setting the input voltage of the user.

In addition, in the present embodiment, 220V / 380V as an input voltage has been described as an example, it will be apparent to those skilled in the art that the same operation can be performed for various input voltages, such as 110V / 220V, 220V / 440V.

In addition, the automatic power switching device of the electric welding machine according to the present invention is configured so that two transformer coils are connected in series or in parallel to one high frequency conversion unit, compared to the conventional technology that constitutes two high frequency conversion units (circuits) The number can be reduced, which can simplify circuit configuration and reduce manufacturing costs.

In the above, the present invention has been illustrated and described with respect to certain preferred embodiments. However, the present invention is not limited to the above-described embodiments, and those skilled in the art to which the present invention pertains can vary as many as possible without departing from the spirit of the present invention as set forth in the claims below. Changes may be made.

1 is an electrical circuit diagram schematically showing a power conversion circuit of a general electric welding machine.

Figure 2 is an exemplary view showing the voltage setting of the power converter in the conventional electric welding machine.

3 is an exemplary view showing another voltage setting of the power converter in the conventional electric welding machine.

Figure 4 is a block diagram schematically showing the configuration of the automatic power conversion device of the electric welding machine according to the present invention.

5 is an electric circuit diagram showing the configuration of a relay control unit of the electric welding machine according to FIG.

6 is an electric circuit diagram showing the configuration of a transformer of the electric welder according to FIG. 4.

7 is an electrical circuit diagram showing a power supply configuration of the electric welder according to FIG. 4.

(Symbols for the main parts of the drawing)

100: variable control unit 110: relay control unit

111: power detector 112: input relay

113: output relay 114: transformer

120: transformer control unit 121: first transformer coil

122: second transformer coil 123: relay for parallel connection

124: relay for serial connection 130: power control unit

131: relay for power selection 132: transformer

a, a ', b, b', c, c ', d, d': contact

1 ', 3': start point 2 ', 4': end point

Claims (5)

Power conversion device for an electric welder having a capacitor for smoothing the ripple voltage of the direct current converted by rectifying the input voltage, and a high frequency converter having first and second transformer coils connected to both ends of the capacitor to generate a high frequency output voltage. as, The primary side of the first transformer coil and the primary side of the second transformer coil are installed in series connection or parallel connection according to the input voltage, and the variable number of the primary windings of the transformer coil varies according to the input voltage. Including a control unit, The variable control unit, A relay controller comparing the input voltage with a preset reference voltage to connect a first contact of the relay if the input voltage is less than the reference voltage, and connect a second contact of the relay if the input voltage is greater than the reference voltage; When the first contact point of the relay is connected, the first and second transformer coils of the high frequency converter are connected in parallel. When the second contact point of the relay is connected, the first and second transformer coils are connected in series. A transformer control unit to enable; And When the first contact of the relay is connected, the first contact of the power source selection relay is connected so that the inverter driving voltage becomes the first driving voltage, and when the second contact of the relay is connected, the inverter driving voltage is second driven. And a power control unit for connecting the second contact of the power selection relay to be a voltage. delete The method of claim 1, The relay control unit, A transformer comprising a primary coil having at least two first and second turns and a secondary coil corresponding to the primary coil; One side of the first contact point and the second contact point are respectively connected to an input power source, the other side of the first contact point is connected to the first winding of the transformer, and the other side of the second contact point is connected to the second winding point of the transformer. relay; A first contact point is connected to a secondary coil corresponding to the first winding of the transformer, and the second contact point is connected to a secondary coil corresponding to the second winding of the transformer; And Compare the input voltage with a preset reference voltage and output a low signal such that the first contact of the input and output relays is connected when the input voltage is less than the reference voltage. And a power detection circuit for outputting a high signal such that the second contact of the secondary relay is connected. The method of claim 1, The transformer control unit connects a point at which the primary winding of the first transformer coil is started to a point at which the primary winding of the second transformer coil is started, an end point at which the primary winding of the first transformer coil is terminated, and the first point. A relay for parallel connection such that an endpoint where the primary winding of the two transformer coils is terminated is connected; And And a series connection relay configured to connect an end point at which the primary winding of the first transformer coil is started and an end point at which the primary winding of the second transformer coil is terminated. The method of claim 1, The power control unit may include a transformer including a primary coil having at least two first and second winding numbers and a secondary coil corresponding to the primary coil; And One side of the first contact point and the second contact point are respectively connected to an input power source, the other side of the first contact point is connected to the first winding of the transformer, and the other side of the second contact point is connected to the second winding of the transformer. Automatic power converter of the electric welder comprising a relay for selection.

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