Energy-saving anti-electric-shock device of electric welding machine

Abstract

The utility model discloses an energy-saving anti-electric-shock device of an electric welding machine, which relates to the technical field of electric welding machines and comprises an electric welding machine circuit and a control circuit, and the electric welding machine circuit comprises a switch QF and a transformer A; the control circuit comprises a transformer TC and a no-load-operation switching circuit; the switch QF is connected with a 380V power supply, and the transformer A is connected with the switch QF in series; a transformer TC is connected in parallel between the switch QF and the transformer A, and the no-load-operation switching circuit is connected in parallel with the transformer TC; and a normally open contact KM1-1 of the no-load-operation switching circuit is arranged between the electric welding machine circuit and the transformer TC control circuit. According to the control circuit designed by the utility model, low voltage is input during no-load, no-load current is smaller, low no-load voltage is output during no-load, input power supply voltage is converted during arc-starting welding, normal operation is realized, and the purposes of safety protection and energy conservation are achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of electric welding machines, in particular to an energy-saving and electric shock-proof device for electric welding machines. Background Art

[0002] An electric welder uses the high-temperature arc generated when the positive and negative poles are short-circuited for an instant to melt the solder on the welding rod and the material to be welded, so that the objects to be contacted are combined; its structure is very simple, which is a high-power transformer; electric welders can generally be divided into two types according to the type of output power supply, one is AC power supply and the other is DC power supply; they use the short circuit between the two poles of the power supply to generate a large amount of arc heat to melt the metal to be welded and the filler metal, so that the objects to be welded are connected together.

[0003] The AC arc welding machine currently used in industry is a relatively simple arc welding transformer, which is directly controlled by a switch. Accidents of electric shock and casualties often occur during use, and the no-load energy consumption is relatively large when not loaded.

[0004] Combined with Figure 1 , the electric welding machine control circuit in the prior art; adopts a simple switch direct control, the secondary side outputs a no-load voltage of about 60-80V, and the transformation ratio is about 6.5; when changing the electrode or carrying the welding handle to move, the human body touches the welding handle and the workpiece, and there is a risk of contact between the human body and the welding handle, and this often occurs during welding operations; during the operation of the welding machine, due to reasons such as changing the welding rod and moving, the no-load time is greater than the welding time, and the temporary load rate is about 35%. When the welding machine is no-load, the no-load loss of the welding machine is about 1% of the welding machine capacity. Taking a 30KVA welding machine as an example, the no-load loss is about 30*1%*8*35%=1.078KWH, that is, the daily loss of each welding machine per working day is about 1.078 kWh.

[0005] Therefore, an energy-saving and electric shock-proof device for welding machines has become a problem that needs to be solved urgently. Utility Model Content

[0006] The technical problem to be solved by the utility model is to increase the control circuit, reduce the energy consumption of the electric welding machine when it is not loaded, and prevent the occurrence of contact injury accidents of the electric welding machine.

[0007] In order to solve the above technical problems, the technical solution provided by the utility model is: an energy-saving and electric shock-proof device for electric welding machine, comprising an electric welding machine circuit and a control circuit, wherein the electric welding machine circuit comprises a switch QF and a transformer A; the control circuit comprises a transformer TC and a no-load-running switching circuit;

[0008] The switch QF is connected to a 380V power supply, and the transformer A is connected in series with the switch QF; a transformer TC is connected in parallel between the switch QF and the transformer A, and the no-load-running switching circuit is connected in parallel with the transformer TC; a normally open contact KM1-1 of the no-load-running switching circuit is provided between the welding machine circuit and the transformer TC control circuit.

[0009] Furthermore, the transformer TC is connected in series with the normally closed contact KM1-2 of the no-load-running switching circuit.

[0010] Furthermore, the no-load-running switching circuit includes an AC contactor KM and a normally open contact KA1 - 1 of a current relay KA. The AC contactor KM is connected in series with the normally open contact KA1 - 1 of the current relay and in parallel with the transformer TC.

[0011] Furthermore, the current relay KA is arranged at the transformer A terminal of the welding machine circuit.

[0012] The advantages of the utility model compared with the prior art are: the control circuit designed by the utility model has a low input voltage when no-load, a small no-load current, a low no-load output voltage when no-load, and converts the input power supply voltage when arc welding to operate normally, thereby achieving the purpose of safety protection and energy saving. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a control circuit schematic diagram of an existing electric welding machine.

[0014] Figure 2 The utility model discloses a circuit diagram of an energy-saving and electric shock-proof device for an electric welding machine. DETAILED DESCRIPTION

[0015] In the description of the present invention, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "inside", "outside", "vertical", "circumferential", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0016] In the present invention, unless otherwise clearly specified and limited, the terms "install", "connect", "connect", "fix" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0017] The energy-saving and electric shock-proof device for welding machine of the utility model is further described in detail below in conjunction with the accompanying drawings.

[0018] Combined with Figure 1-2 , the utility model is introduced in detail.

[0019] The utility model uses the normally open and normally closed contacts of the AC contactor to complete the switching of the input power supply voltage, and the current relay senses the output side current. When the induced current reaches a certain value, the current relay dry node flips, and its normally open contact closes, controlling the AC contact to pull in, so as to achieve circuit switching.

[0020] The specific implementation process of the energy-saving and electric shock-proof device for welding machines of the utility model is as follows:

[0021] Combined with Figure 2 The utility model adds a control circuit on the basis of the existing electric welding machine circuit. Taking the BX1-500 electric welding machine as an example, when the electric welding machine is not loaded, the power supply is supplied to the primary side of the electric welding machine through the 36V control transformer TC and the normally closed contact of the AC contactor KM. The transformation ratio of the welding machine is about 6.5, and the secondary side of the welding machine outputs a voltage of about 6V, which is a safe voltage to ensure the safety of the staff; the no-load loss is reduced to 36V by the voltage, and the actual loss is the loss of the no-load transformer, which is about 1% of the capacity of the welding machine. The actual loss is less than 10% of the original loss, and the energy saving is more than 90%.

[0022] When the welding arc is ignited, the electrode contacts the workpiece, and the no-load voltage of the secondary side of the welding machine is about 6V. Through the welding handle wire, welding clamp, welding rod, workpiece, and welding machine grounding wire, a closed loop is formed. The resistance of this loop is about 0.5~0.6Ω, and there is about 10A current on the secondary side, which triggers the normally open contact KA1-1 of the current relay KA to flip and close, and connect the AC contactor KM circuit. The AC contactor KM is attracted, and its normally closed contact KM1-2 is disconnected and the normally open contact KM1-1 is closed, cutting off the 36V power supply of the primary side of the welding machine, and connecting the 380V power supply of the primary side of the welding machine, and the welding machine works. When the welding is finished, the current is zero, and the current relay KA flips again and returns to the no-load state.

[0023] The above description of the utility model and its implementation methods is not restrictive. The drawings show only one implementation method of the utility model, and the actual structure is not limited thereto. In short, if ordinary technicians in this field are inspired by it and design structural methods and embodiments similar to the technical solution without creativity without departing from the purpose of the invention of the utility model, they should all fall within the protection scope of the utility model.

Claims

1. An energy-saving and electric shock-proof device for a welding machine, comprising a welding machine circuit and a control circuit, wherein the welding machine circuit comprises a switch QF and a transformer A; characterized in that: The control circuit includes a transformer TC and a no-load-running switching circuit; The switch QF is connected to a 380V power supply, and the transformer A is connected in series with the switch QF; a transformer TC is connected in parallel between the switch QF and the transformer A, and the no-load-running switching circuit is connected in parallel with the transformer TC; a normally open contact KM1-1 of the no-load-running switching circuit is provided between the welding machine circuit and the transformer TC control circuit.

2. The energy-saving and electric shock-proof device for welding machine according to claim 1, characterized in that: The transformer TC is connected in series with the normally closed contact KM1-2 of the no-load-running switching circuit.

3. The energy-saving and electric shock-proof device for welding machine according to claim 2, characterized in that: The no-load-running switching circuit includes an AC contactor KM and a normally open contact KA1 - 1 of a current relay KA. The AC contactor KM is connected in series with the normally open contact KA1 - 1 of the current relay and is connected in parallel with a transformer TC.

4. The energy-saving and electric shock-proof device for welding machine according to claim 3 is characterized in that: The current relay KA is arranged at the transformer A terminal of the welding machine circuit.

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