JP5157270B2 - Non-consumable electrode type automatic welding equipment - Google Patents

Description

  The present invention relates to a non-consumable electrode type automatic welding apparatus that performs welding by selecting one welding condition from among a plurality of welding conditions.

  Non-consumable electrode type welding (TIG welding) is a method in which an arc is generated using a tungsten electrode that is not easily consumed by heat, and welding is performed by flowing an inert gas such as argon or helium around the arc. And the arc is stable, and it is used for welding stainless steel or aluminum alloy. In non-consumable electrode type welding, a welding current command value is designated as a welding command condition, and the welding machine performs constant current control so as to keep the welding current constant. Then, in order to obtain the welding amount in the work piece, welding is performed while supplying a rod-like filler material to the molten pool of the work piece melted by the arc, but the supply amount of the filler material is adjusted. By doing so, the amount of welding can be controlled. If the amount of filler material supplied is large, the melt of the filler material is insufficiently melted, and if the amount of filler material supplied is small, a uniform bead cannot be obtained.

  Regarding the supply of the filler material, in the case of manual welding, the operator holds the rod-like filler material in his hand and supplies the filler material directly to the arc portion. In addition, in the case of an automatic welding apparatus, a filler material supply device configured by a motor or the like is used to automatically supply a filler material. Feeding material is supplied. The filler metal must be fed at a constant supply amount, but there is no direct causal relationship with the real-time welding current output feedback or welding voltage output feedback in welding control, that is, the welding current or welding voltage is Even if it fluctuates somewhat, the filler metal is supplied at a constant supply amount. In many cases, the filler supply amount input by the operator is generally determined experimentally or empirically by observing a weld bead after actual welding.

  In general, in non-consumable electrode type welding, the tip of the non-consumable electrode and the surface of the work piece are utilized by utilizing the fact that the welding voltage is approximately proportional to the distance between the tip of the non-consumable electrode and the surface of the work piece. Automatic voltage control is performed to keep the welding voltage constant by moving the torch in a direction perpendicular to the surface of the work piece so that the interval between them is constant. In general, a high-frequency spark is used to generate an arc between the non-consumable electrode and the workpiece. Therefore, adjust the position of the welding torch where the non-consumable electrode is attached so that the distance between the tip of the non-consumable electrode and the surface of the work piece is small, It must be easy to generate an arc following the dielectric breakdown. In many cases, the target voltage value when the welding voltage is held constant is usually designated by an operator, or the target voltage value is obtained by sampling the welding voltage at the start of welding or during welding. When the operator designates input, welding is performed once to measure the welding voltage, and then the measured welding voltage is input as a target value.

  In a conventional welding apparatus, an initial condition setting signal for welding and a phenomenon signal (actual welding voltage, welding current, etc.) obtained by welding performed based on this initial condition are stored in the storage means. Then, when starting welding next, the initial condition setting signal is first read from the storage means, and welding is started based on that signal. After a predetermined time has elapsed, the phenomenon signal is read from the storage means and used as a direct welding condition signal. There is a technology to control to match it. Then, the welding is actually performed, the welding output is stabilized by feedback control, the condition setting signal at that time is stored in the storage means, and for the subsequent welding, the stored condition setting signal is reproduced and welded. There are some which replace the signal of the condition setting means and control the welding operation using this as a target value. Furthermore, if necessary, it is possible to switch and apply the signal of the storage means to a measuring instrument that displays the welding phenomenon value attached to the welding apparatus, so that it is possible to confirm that the setting is appropriate without energizing the welding. (For example, refer to Patent Document 1).

For conventional automatic voltage control, a switching switch circuit is provided in the drive mechanism that drives the welding torch. At the start of welding, the interval between the tip of the non-consumable electrode and the surface of the work piece is subject to high-frequency sparks and arcs. Adjust the interval so that it becomes easy, and after the arc has stabilized, increase the arc length and move to arc length control smoothly, or temporarily interrupt the welding voltage control to control the position of non-consumable electrodes. The arc length is changed positively to change the arc heat or the arc spread and control according to the change of welding conditions.When returning from the welding voltage control at the end of welding to the torch position control, There is one having a mechanism that makes a large interval so that the tip of the non-consumable electrode does not come into contact with the surface of the weldment (see, for example, Patent Document 2).
Japanese Patent Publication No. 63-19268 Japanese Patent Publication No. 61-53150

  However, in the conventional non-consumable electrode type welding apparatus, the welding current value with respect to the filler material supply amount, the welding material, the diameter of the filler material, the distance between the non-consumable electrode and the filler material, and between the non-consumable electrode and the work piece The distance is determined by the operator experimentally or empirically, and welding is performed. Therefore, it is difficult to easily and stably maintain a high quality welding quality.

  Further, in a conventional non-consumable electrode type welding apparatus, welding is performed by moving the welding torch in a direction perpendicular to the surface of the work piece so that the distance between the tip of the non-consumable electrode and the surface of the work piece is constant. When performing automatic voltage control to keep the voltage constant, the target voltage value is usually determined experimentally or empirically by the operator, so that the tip of the non-consumable electrode can be easily and stably determined. It was difficult to keep the distance between the surfaces of the workpieces constant.

  The present invention provides an automatic welding apparatus that selects one welding condition from a plurality of welding conditions stored in a welding condition storage unit based on a welding current value and performs welding control and filler material feeding. In addition, one reference voltage value is selected from a plurality of welding conditions stored in the welding condition storage unit based on the welding current value, and the reference voltage value and the actual welding arc voltage value are held constant. An object is to provide a non-consumable electrode type automatic welding apparatus.

  In order to solve the above problems, an automatic welding apparatus of the present invention includes a welding torch having a non-consumable electrode, a filler material feeding unit that feeds a filler material to a welding object, and the non-consumable electrode. A power supply unit that supplies electric power to the welding object, a welding current value input unit for inputting a welding current value for performing welding, and at least a welding current value and a filler material feeding amount are associated with each other. A welding condition storage unit that stores a plurality of welding conditions, and one welding condition is selected from a plurality of welding conditions stored in the welding condition storage unit based on a welding current value input by the welding current value input unit A control unit configured to control the power supply unit and the filler material feeding unit based on a welding current value input by the welding current value input unit and a filler material feeding amount of a selected welding condition. It is controlled and welded.

  And by this structure, a control part selects one welding condition from the some welding conditions memorize | stored in the welding condition memory | storage part based on the welding current value input by the welding current value input part, and is a power supply part. Welding is performed by controlling the filler material feeding section.

  Further, in addition to the above, the automatic welding apparatus of the present invention has at least a welding current value and a filler material associated with at least a welding current value stored in the welding condition storage unit and a filler material feed amount. It consists of a table in which the feeding amount is associated, or at least a first-order mathematical expression in which at least the welding current value is associated with the filler material feeding amount.

  With this configuration, the filler material feed amount can be selected based on the input welding current value.

  Further, in addition to the above, the automatic welding apparatus of the present invention can set one welding condition from a plurality of welding conditions stored in the welding condition storage unit based on the welding current value input by the welding current value input unit. Equipped with a display that displays the selected filler material feed amount and a filler material feed amount input unit for entering the filler material feed amount. Enter any filler material feed amount. It can be done.

  With this configuration, the operator can input an arbitrary amount of filler material feeding using the filler material supply amount displayed on the display unit as a guide.

  In addition to the above, the automatic welding apparatus of the present invention further includes an actuator for moving the welding torch, and a voltage detection unit for detecting a voltage between the non-consumable electrode provided on the welding torch and the welding object. A plurality of welding conditions in which at least a welding current value and a reference welding voltage value are associated with each other are stored in the welding condition storage unit, and at least the welding current value and the reference welding voltage value stored in the welding condition storage unit are stored. The associated welding conditions are composed of a table in which at least the welding current value and the reference welding voltage value are associated with each other, or at least a first-order mathematical expression in which the welding current value and the reference welding voltage value are associated with each other. A reference welding voltage value is derived by selecting one welding condition from a plurality of welding conditions stored in the welding condition storage unit based on the welding current value input by the value input unit, and the voltage Out section is to perform welding while controlling the actuator so that the reference welding voltage value derived as voltage detected becomes equal.

  And by this structure, a control part is from among the several welding conditions memorize | stored in the welding condition memory | storage part based on the voltage value which a voltage detection part detects, and the welding current value input by the welding current value input part. By performing welding while controlling the actuator so that the reference voltage value derived by selecting one welding condition becomes equal, the operator can start welding without specifying the target voltage value. Without sampling the welding voltage during or during welding, the reference voltage value according to the welding material, the diameter of the filler metal, the distance between the electrode and the filler metal, the distance between the electrode and the work piece, etc. The voltage between the consumable electrode and the workpiece can be controlled, that is, the distance between the welding torch and the workpiece can be controlled.

  Further, in addition to the above, the automatic welding apparatus of the present invention can set one welding condition from a plurality of welding conditions stored in the welding condition storage unit based on the welding current value input by the welding current value input unit. It has a display unit that displays the reference welding voltage value that has been selected and derived, and a reference welding voltage value input unit for inputting the reference welding voltage value, and the control unit detects the input reference welding voltage value and the voltage detection unit. The welding is performed while controlling the actuator so that the detected voltage value is equal.

  With this configuration, the operator can input the target voltage value for controlling the welding voltage between the non-consumable electrode and the workpiece to be fixed, using the reference voltage value displayed on the display unit as a guideline. The voltage between the non-consumable electrode and the work piece, that is, the distance between the welding torch and the work piece can be controlled so that the set target voltage value and the actual welding arc voltage are the same.

  As described above, the present invention stores a plurality of welding conditions in which a welding current value and a filler material feeding amount are associated with each other, and allows the filler material feeding amount to be selected based on the welding current value. Selection of the material feeding amount can be easily performed, and convenience can be improved and weldability can be improved.

  Hereinafter, the best mode for carrying out the present invention will be described with reference to FIGS.

(Embodiment 1)
In FIG. 1, reference numeral 1 denotes a control device that controls an actuator 23 described later. Reference numeral 11 denotes a welding current value input unit for an operator to input a welding current value for performing welding, and includes a general-purpose input device such as a key, a dial, or a touch panel. Reference numeral 12 denotes a welding condition storage unit that stores a plurality of welding conditions in which at least a welding current value and a filler material feed amount are associated with each other. Reference numeral 13 denotes a voltage detection unit that detects a voltage between a non-consumable electrode attached to the welding torch 19 and an object to be welded 20 that is an object to be welded, and includes a voltage measurement sensor and the like. A power supply unit 14 supplies power between the non-consumable electrode and the welding object, and controls the welding current by thyristor type phase control or inverter type power control. 15 displays a filler material feed amount derived by selecting one welding condition from a plurality of welding conditions by the control unit 18 to be described later, or one welding condition from a plurality of welding conditions. The display unit displays a reference voltage value that is selected and derived, and includes a 7-segment display LED, a general-purpose liquid crystal display device, and the like. Reference numeral 16 denotes a filler material feed amount input unit for an operator to input a filler material feed amount, which is composed of general-purpose input devices such as keys, dials, and touch panels. Reference numeral 17 denotes a welding voltage value input unit for an operator to input a welding voltage value, which includes a general-purpose input device such as a key, a dial, or a touch panel. Reference numeral 18 designates one welding condition from among a plurality of welding conditions stored in the welding condition storage unit based on the welding current value input by the welding current value input unit, and the power source unit 14 or a filler material feed described later. It is a control part which controls the supply part 22, the actuator 23, etc., and is comprised with semiconductor components, such as CPU. Reference numeral 19 denotes a welding torch having a non-consumable electrode. Reference numeral 20 denotes a workpiece. 21 is a filler material for adjusting the welding amount. Reference numeral 22 denotes a filler material feeding unit that feeds a filler material to a welding location, and is constituted by a feeding motor with a guide roller. Reference numeral 23 denotes an actuator that holds the welding torch and moves the welding torch. An example of the actuator is an articulated industrial robot.

  An operation example of the automatic welding apparatus configured as described above will be described. An operator inputs a welding current value for performing welding, for example, 200 A using the welding current value input unit 11. At this time, the welding material, the diameter of the filler material, the distance between the non-consumable electrode and the filler material, the distance between the electrode and the workpiece, and the like are set in advance by the operator. The welding condition storage unit 12 stores a welding condition in which a welding current value and a filler material feeding amount are associated with each other. An example of data stored in FIG. 2 is shown. In the example of FIG. 2, the relationship between the welding current value and the filler material supply amount is stored as an approximate expression of the first or higher order. For example, the welding material is iron, the filler material diameter is 0.9 mm, and the non-consumable electrode and the molten metal supply amount. The welding current value and the amount of filler material supplied when the distance between the filler metals is 1.0 mm and the distance between the non-consumable electrode and the workpiece is 3.0 mm are shown. The welding condition storage unit 12 stores a plurality of such approximate expressions so that various materials, wire diameters, and the like can be handled. In FIG. 2, for example, when the welding current value is 200 A, the filler material supply amount is 4.0 m / min. In the example of FIG. 3, the relationship between the welding current value and the filler material supply amount is stored in a table, and the filler material supply amount when the welding current value is 200 A is 4.0 m / min. . In this way, the control unit 18 selects one welding condition from the plurality of welding conditions stored in the welding condition storage unit 12 based on the input welding current value, and supplies power so that the welding current becomes 200A. The part 14 is controlled, and the filler material supply part 22 is further controlled so that the filler material supply rate is 4.0 m / min.

  As described above, according to the present embodiment, the control unit 18 determines the filler material supply amount based on the input welding current value, and controls the power supply unit 14 and the filler material supply unit 22. Conventionally, the amount of filler material supplied was determined by the operator through experiments or empirical rules. In the present embodiment, however, the welding material and the filler amount are determined based on the welding current value specified by the operator. By deriving the feed amount of the filler metal according to the diameter of the material, the distance between the electrode and the filler metal, the distance between the electrode and the work piece, the welding control and the filler material feed amount are controlled. It is possible to perform the best welding by supplying the filler metal with a suitable amount of filler material supplied.

  In TIG welding, the amount of filler material suitable for welding varies depending on the condition of the object to be welded, and it is difficult to select a suitable amount of filler material. Although it is very difficult if it is shallow, a plurality of welding conditions in which the welding current value and the filler material feeding amount are associated are stored as in the present embodiment, and the filler material feeding amount is determined by the welding current value. Therefore, it is possible to easily select the filler material feeding amount, and the convenience can be improved and the weldability can be improved.

(Embodiment 2)
In the present embodiment, the same parts as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted. The difference from the first embodiment is that the selected filler material supply amount is displayed on the display unit 15 and the filler material supply amount input unit 16 can be used to input the filler material supply amount. It is.

  The welding current value for the operator to perform welding is input, for example, 200 A using the welding current value input unit 11. At this time, the welding material, the diameter of the filler material, the distance between the electrode and the filler material, the distance between the electrode and the workpiece to be welded, etc. are set in advance. The welding condition storage unit 12 stores a welding condition in which a welding current value and a filler material feeding amount are associated with each other. The method for selecting the filler material feed amount from the welding current value is the same as the method of the first embodiment. The selected filler material supply amount is displayed on the display unit 15. The operator inputs an arbitrary amount of filler material supply using the filler material supply amount input unit 16 with the filler material supply amount displayed on the display unit 15 as a guide. The control unit 18 controls the filler material feeding unit 22 so that the supplied filler material supply amount is obtained.

  As described above, according to the present embodiment, the filler material supply amount selected based on the welding current value is displayed, and the operator can input the filler material supply amount. The operator can know the amount of filler material that can be used as a guide, and also observe the degree of welding while actually welding, and supply the filler material with the ideal amount of filler material. Can be welded.

(Embodiment 3)
In the present embodiment, the same parts as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted. The difference from the first embodiment is that at least a welding current value and a reference welding voltage value are associated and stored as welding conditions, a reference welding voltage value is selected based on the welding current value, and the detected welding voltage is the reference voltage. The control unit 18 controls the actuator 23 so that they are equal to each other so that the distance between the tip of the non-consumable electrode and the surface of the welding object is a predetermined distance.

  The welding current value for the operator to perform welding is input, for example, 200 A using the welding current value input unit 11. At this time, the welding material, the diameter of the filler material, the distance between the non-consumable electrode and the filler material, the distance between the non-consumable electrode and the workpiece to be welded, etc. are set in advance. The welding condition storage unit 12 stores at least welding conditions in which a welding current value and a reference welding voltage value are associated with each other. FIG. 4 shows an example of stored data. In the example of FIG. 4, the relationship between the welding current value and the reference welding voltage value is stored as a first-order or higher approximation formula. For example, the welding material is iron, the filler metal diameter is 0.9 mm, and the electrode and filler metal. The relationship between the welding current value and the reference welding voltage value when the distance between them is 1.0 mm and the distance between the non-consumable electrode and the workpiece is 3.0 mm is shown. The reference welding voltage value when the welding current value is 200 A is 16.0V. In the example of FIG. 5, the relationship between the welding current value and the reference welding voltage value is stored in a table, and the reference welding voltage value when the welding current value is 200 A is 16.0V. In this way, the control unit 18 selects one welding condition from the plurality of welding conditions stored in the welding condition storage unit 12 based on the input welding current value, derives a reference welding voltage value, and detects the voltage. The actuator 23 to which the welding torch 19 is attached is operated so that the welding voltage value measured by the unit 13 and the reference welding voltage value 16.0 V derived from the welding condition storage unit 12 coincide.

  As described above, according to the present embodiment, the control unit 18 determines the reference welding voltage value based on the input welding current value, and controls and operates the actuator 23 to which the welding torch 19 is attached. Conventionally, the operator inputs or designates the welding voltage at the start of welding or sampling the welding voltage during welding to obtain the target value, or once welding is performed and the welding voltage is measured and then the measured welding is performed. Based on the welding current specified by the operator, the voltage was set as the target value, depending on the welding material, the diameter of the filler metal, the distance between the electrode and the filler material, the distance between the electrode and the workpiece, etc. By deriving the reference voltage value and controlling the welding control and the actuator, the welding voltage can be kept constant.

(Embodiment 4)
In the present embodiment, the same parts as those in the third embodiment are denoted by the same reference numerals, and detailed description thereof is omitted. The difference from the third embodiment is that the reference welding voltage value selected from the welding current value is displayed and the operator can input the target voltage value. As a result, the operator can know the reference welding voltage value as a guide, and can observe the degree of automatic voltage control while actually welding, and can perform the best welding with an ideal welding voltage.

  The welding current value for the operator to perform welding is input, for example, 200 A using the welding current value input unit 11. At this time, the welding material, the diameter of the filler material, the distance between the electrode and the filler material, the distance between the electrode and the workpiece to be welded, etc. are set in advance. The welding condition storage unit 12 stores a welding condition in which a welding current value is associated with a reference welding voltage value. The method for selecting the reference welding voltage value from the welding current value is the same as the method described in the third embodiment. The selected reference welding voltage value is displayed on the display unit 15. The operator inputs a target welding voltage value using the welding voltage value input unit 17 with the reference welding voltage value displayed on the display unit 15 as a guide. The control unit 18 operates the actuator 23 to which the welding torch 19 is attached so that the welding voltage value measured by the voltage detection unit 13 and the target voltage value input by the welding voltage input unit 17 coincide with each other during welding. Let

  The automatic welding apparatus according to the present invention is based on the welding current specified by the operator, the welding material, the diameter of the filler metal, the distance between the electrode and the filler material, the distance between the electrode and the workpiece, and the like. By deriving the feed amount and controlling the welding control and the feed rate of the filler material, it is possible to supply the filler material with the ideal filler material supply amount and perform the best welding. In automatic voltage control that keeps the voltage constant, a reference voltage value that is the target of automatic voltage control is derived based on the welding current specified by the operator, and the non-consumable electrode and workpiece to be welded are targeted with the derived reference voltage value as a target. As a non-consumable electrode type welding device that can control the welding voltage between the two, that is, the distance between the non-consumable electrode and the work piece, and select one welding condition from a plurality of welding conditions. It is useful above.

Basic configuration diagram of Embodiments 1 to 4 of the present invention The figure which shows the example of the approximate expression in Embodiment 1 of this invention The figure which shows the example of the table in Embodiment 1 of this invention. The figure which shows the example of the approximate expression in Embodiment 3 of this invention The figure which shows the example of the table in Embodiment 3 of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Control apparatus 11 Welding current value input part 12 Welding condition memory | storage part 13 Voltage detection part 14 Power supply part 15 Display part 16 Filling material feed amount input part 17 Welding voltage value input part 18 Control part 19 Welding torch 20 Workpiece 21 Filler material 22 Filler material feed section 23 Actuator

Claims (1)

A welding torch with non-consumable electrodes;
A filler material feeding section for feeding a filler material to a welding object;
A power supply for supplying power between the non-consumable electrode and the welding object;
A welding current value input section for inputting a welding current value for performing welding,
A welding condition storage unit that stores a plurality of welding conditions in which at least a welding current value and a filler material feeding amount are associated with each other;
A control unit that selects one welding condition from a plurality of welding conditions stored in the welding condition storage unit based on a welding current value input by the welding current value input unit;
The control unit performs welding by controlling the power supply unit and the filler material feeding unit based on the welding current value input by the welding current value input unit and the filler material feeding amount of the selected welding condition. ,
The welding condition that associates at least the welding current value and the filler material feeding amount stored in the welding condition storage unit is a table that associates at least the welding current value and the filler material feeding amount, or at least the welding current value. And a primary or higher mathematical formula that associates the filler material feed amount,
The filler material feed amount derived by selecting one welding condition from a plurality of welding conditions stored in the welding condition storage unit based on the welding current value input by the welding current value input unit is displayed. And a filler material feeding amount input unit for inputting a filler material feeding amount, and an arbitrary filler material feeding amount can be input.
An actuator for moving the welding torch;
A voltage detection unit for detecting a voltage between a non-consumable electrode provided on the welding torch and a welding object;
A plurality of welding conditions in which at least a welding current value and a reference welding voltage value are associated with each other are stored in the welding condition storage unit,
The welding condition associated with at least the welding current value and the reference welding voltage value stored in the welding condition storage unit is a table in which at least the welding current value and the reference welding voltage value are associated, or at least the welding current value and the reference welding voltage. It consists of a mathematical expression that is associated with a value
The control unit selects one welding condition from a plurality of welding conditions stored in the welding condition storage unit based on the welding current value input by the welding current value input unit, and sets a reference welding voltage value. deriving, a display unit for displaying the reference welding voltage value behind the derivations,
After the reference welding voltage value derived is displayed, as a guideline the reference welding voltage value displayed, includes a welding voltage value input unit for inputting a target voltage value is a welding voltage value of the target,
The control unit is a non-consumable electrode type automatic welding apparatus that performs welding while controlling the actuator so that an input target voltage value is equal to a detection voltage value detected by the voltage detection unit.

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