JP3907848B2 - Power supply for arc welding - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention comprises a measuring means for measuring a plurality of physical quantities, a comparing means for comparing a value based on the measured physical quantities with an allowable value for each management item, and an abnormal indicator lamp, and a value based on the measured physical quantities. The present invention relates to a power source for arc welding in which the abnormality indicator lamp is lit when any of the allowable values is exceeded.
[0002]
[Prior art]
The power source for arc welding is a device that supplies electric power necessary for welding in order to perform arc welding. Such an arc welding power source will be described with reference to FIG.
FIG. 3 is a connection diagram of a conventional arc welding power source. In the figure, reference numeral 1 denotes a power source for arc welding, which is connected to a commercial frequency AC power source 2 and includes a power source 3 composed of a transformer, a rectifying element and the like, and a protection switch disposed between the power source 3 and the welding load 6. 4 and a welding start switch 5, a control unit 7 for controlling the power supply unit 3 and the switch 4, etc., and a condition setting unit 8 etc. for setting the magnitude of the output supplied to the welding load 6 are provided. ing. In addition, the arc welding power source 1 includes a voltage detection circuit 9 for measuring the voltage Vi of the AC power source 2, a temperature sensor 10 that outputs a signal when the temperature of the power source unit 3 exceeds a predetermined temperature, and a control unit 7. An abnormality indicator lamp 12 or the like is provided via a switch 11 that controls the above.
[0003]
The control unit 7 is provided with a comparison circuit. When the voltage Vi measured as a physical quantity exceeds 1.1 times the rated voltage, it is overvoltage, and when the voltage Vi is less than 0.9 times the rated voltage, the voltage is insufficient. In any case, the abnormality indicator lamp 12 is turned on as an abnormal state. The abnormality indicator lamp 12 is also turned on when the temperature sensor 10 outputs a signal t.
[0004]
Next, the lighting procedure of the abnormality indicator lamp 12 in the conventional arc welding power source will be described.
FIG. 4 is a flowchart showing a procedure for lighting a conventional abnormality indicator lamp. When a start switch (not shown) is turned on, the control unit 7 first compares the voltage Vi of the AC power supply 2 detected by the voltage detection circuit 9 with a voltage 1.1 times the rated voltage V (procedure S100), and Vi ≦ 1. In the case of 1V, the process of step S110 is performed, and in the case of Vi> 1.1V, the process of step S130 is performed. In step S110, the voltage Vi is compared with 0.9 times the rated voltage V. If Vi ≧ 0.9V, the process of step S120 is performed, and if Vi <0.9V, the process of step S130 is performed. In step S120, the presence / absence of the signal t from the temperature sensor 10 is confirmed. If the signal t is present, the process of step S130 is performed. If the signal t is not present, the process of step S100 is performed.
[0005]
In step S130, the switch 4 is opened, the switch 11 is closed, and the abnormality indicator lamp 12 is turned on (step S140). Then, the voltage Vi is compared with 1.1 times the rated voltage V (step S150), and Vi ≦ If 1.1V, the process of step S160 is performed. If Vi> 1.1V, the process of step S150 is performed. In step S160, the voltage Vi is compared with a voltage 0.9 times the rated voltage V. If Vi ≧ 0.9V, the process of step S170 is performed, and if Vi <0.9V, the process of step S150 is performed. In step S170, the presence / absence of the signal t from the temperature sensor 10 is confirmed. If the signal t is present, the process of step S150 is performed. If the signal t is not present, the switch 4 is closed (step S180) and the switch 11 is opened. After the indicator lamp 12 is turned off (procedure S190), the process of procedure S100 is performed.
[0006]
As a result, a desired range of output could be supplied to the welding load 6 and the welding quality could be made appropriate. In addition, the power source unit 3 can be prevented from being damaged by heat and the maintenance of the arc welding power source 1 can be facilitated, and the life thereof can be extended.
[0007]
[Problems to be solved by the invention]
The switch 4 is opened even during the welding operation. Therefore, when welding cannot be performed, the operator checks whether the abnormality indicator lamp 12 is lit. For example, when the power supply unit 3 is heated, the temperature hardly decreases immediately, so that the abnormality indicator lamp 12 can be turned on. However, when the voltage Vi instantaneously becomes an abnormal voltage (in the above case, when the voltage Vi deviates from the rated voltage ± 10%), the abnormality indicator lamp 12 is turned off at the same time when the voltage Vi returns to the allowable range. The operator could not confirm the abnormal state. In addition, since a plurality of abnormal states are displayed by one abnormal indicator lamp, it took time to elucidate the cause of the abnormal state that occurred. Furthermore, since the switch 11 is controlled to be opened and closed by the control unit 7, the switch 11 is reset when the power of the control unit 7 is turned off.
[0008]
An object of the present invention is to provide a power source for arc welding that solves the above-described problems in the prior art, can immediately confirm the contents of an abnormal state that has occurred, and can quickly implement measures to prevent the occurrence of the abnormality. It is in.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, the present invention comprises a measuring means for measuring a plurality of physical quantities, a comparing means for comparing a value based on the measured physical quantities with an allowable value for each management item, and an abnormality indicator lamp, In the arc welding power source in which the abnormality indicator lamp is turned on when any of the measured values based on the physical quantity exceeds the allowable value, a storage means is provided for storing the occurrence of the abnormality, and the storage means is generated. Even when the abnormality is released, the management item exceeding the allowable value is continuously stored .
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described based on the illustrated embodiments.
FIG. 1 is a connection diagram of a power source for arc welding according to the present invention. Components having the same or the same functions as those in FIG. In the figure, reference numerals 21 to 25 denote abnormal history display lamps which are arranged on a printed circuit board (not shown) of the control unit 7 and are connected to a control power supply (not shown) via toggle switches 31 to 35. Reference numerals 41 to 45 denote actuators, each of which includes a coil, a shaft, and a spring that urges the shaft toward the inside of the actuator. When turned on, that is, when a voltage is applied to each coil, each shaft is a spring. It is designed to jump out a predetermined length against this. The actuators 41 to 45 are arranged at positions where the toggle switches 31 to 35 can be turned on when the actuators 41 to 45 are turned on.
[0011]
Reference numeral 50 denotes a current detector composed of a shunt or a transformer, which detects the value of the current I flowing through the load 6 (hereinafter referred to as a current value), which is a physical quantity, and outputs the result to the control unit 7. An arithmetic circuit and a timer (not shown) provided in the control unit 7 calculate the usage rate based on the input current value, and the current value is equal to or greater than a predetermined value (for example, twice the rated current). The signal m is output to the comparison circuit as an overcurrent when it continues for a predetermined time (for example, 2 seconds), and the signal n is output to the comparison circuit when the usage rate is exceeded.
[0012]
Next, the operation of the present invention will be described.
FIG. 2 is a flowchart showing a lighting procedure of the abnormality history indicator lamp. When a start switch (not shown) is turned on, the control unit 7 first compares the voltage Vi detected by the voltage detection circuit 9 with a voltage 1.1 times the rated voltage V (step S200), and if Vi ≦ 1.1V Performs the process of step S210. If Vi> 1.1V, the actuator 41 is turned on for a predetermined time (step S250), and then the process of step S400 is performed. When the actuator 41 is turned on, the toggle switch 31 is closed and the abnormality history indicator lamp 21 is lit.
[0013]
In step S210, the voltage Vi is compared with a voltage 0.9 times the rated voltage V. If Vi ≧ 0.9V, the process of step S220 is performed. If Vi <0.9V, the actuator 42 is turned on for a predetermined time. After that (procedure S260), the process of procedure S400 is performed. When the actuator 42 is turned on, the toggle switch 32 is closed and the abnormality history display lamp 22 is lit.
[0014]
In step S220, the presence or absence of the signal t from the temperature sensor 10 is confirmed. If the signal t is not present, the process of step S230 is performed. If the signal t is present, the actuator 43 is turned on for a predetermined time (step S270). The process of step S400 is performed. When the actuator 43 is turned on, the toggle switch 33 is closed and the abnormality history display lamp 23 is lit.
[0015]
In step S230, the presence / absence of the signal m is checked. If the signal m is not output, the process of step S240 is performed. If the signal m is output, the actuator 44 is turned on for a predetermined time (step S280). The process of step S400 is performed. When the actuator 44 is turned on, the toggle switch 34 is closed and the abnormality history display lamp 24 is lit.
[0016]
In step S240, the presence / absence of the signal n is confirmed. If the signal n is not output, the process of step S200 is performed. If the signal n is output, the actuator 45 is turned on for a predetermined time (step S290). The process of step S400 is performed. When the actuator 45 is turned on, the toggle switch 35 is closed and the abnormality history display lamp 25 is lit.
[0017]
In step S400, the switch 4 is opened, the switch 11 is closed and the abnormality indicator lamp 12 is turned on (step S410). Then, the voltage Vi is compared with 1.1 times the rated voltage V (step S420), and Vi ≦ If 1.1V, the process of step S430 is performed, and if Vi> 1.1V, the process of step S420 is performed. In step S430, the voltage Vi is compared with a voltage 0.9 times the rated voltage V. If Vi ≧ 0.9V, the process of step S440 is performed, and if Vi <0.9V, the process of step S420 is performed. In step S440, the presence or absence of the signal t from the temperature sensor 10 is confirmed. If there is no signal t, the process of step S450 is performed, and if the signal t is present, the process of step S420 is performed. In step S450, the switch 4 is closed, the switch 11 is opened, the abnormality indicator lamp 12 is turned off (step S460), and the process of step S200 is performed.
[0018]
As a result, even when the abnormality indicator lamp 12 is turned off, the abnormality history can be confirmed by referring to the presence or absence of the abnormality history indicator lamps 21 to 25 being turned on. That is, when the abnormality history indicator lamp 21 is lit, an overvoltage has occurred, and when the abnormality history indicator lamp 22 is lit, a voltage shortage has occurred. When the abnormality history indicator lamp 24 is lit, an overcurrent has occurred. When the abnormality history indicator lamp 25 is lit, the usage rate is exceeded. It is possible to confirm that an overshoot has occurred. And since the toggle switches 31-35 maintain the state at that time even if the power supply of the control part 7 is turned off, the maintenance staff or the operator confirms the lighting of the abnormality history display lamps 1-25 to ensure Therefore, it is possible to grasp the cause of abnormalities and immediately consider countermeasures. If the cause of the abnormality is grasped, the toggle switches 31 to 35 that have been turned on may be manually turned off.
[0019]
In the above, the toggle switches 31 to 35 are employed as the storage means for the abnormal state. However, an electrical storage circuit such as a rewritable nonvolatile memory is provided, and the abnormal state is stored in the storage circuit. You may make it light the abnormality log | history display lamps 21-25 according to the content.
[0020]
Moreover, although the abnormality log | history display lamps 21-25 were arrange | positioned on the printed circuit board, you may arrange | position to the position which can be easily seen from the outside, and may increase a management item further.
[0021]
Further, the present invention can be applied not only to a power source for arc welding but also to an arc cutting machine.
[0022]
【The invention's effect】
As described above, according to the present invention, since the continued storage of management items exceeds the allowable value when the abnormality occurred is released, can grasp the cause of reliably abnormal, immediately measures Can be considered.
[Brief description of the drawings]
FIG. 1 is a connection diagram of an arc welding power source according to the present invention.
FIG. 2 is a flowchart showing a lighting procedure of an abnormality history indicator lamp.
FIG. 3 is a connection diagram of a conventional arc welding power source.
FIG. 4 is a flowchart showing a procedure for lighting a conventional abnormality indicator lamp.
[Explanation of symbols]
12 Abnormality indication lamps 21-25 Abnormality history indication lamps 31-35 Toggle switches 41-45 Actuator

Claims (1)

A measuring means for measuring a plurality of physical quantities, a comparing means for comparing a value based on the measured physical quantities with an allowable value for each management item, and an abnormal indicator lamp, and any one of the values based on the measured physical quantities is In the arc welding power source that turns on the abnormality indicator when the allowable value is exceeded,
A storage means for storing the occurrence of the abnormality is provided,
The power source for arc welding is characterized in that the storage means continues to store the management item exceeding the allowable value even when the abnormality that has occurred is canceled.

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