Arc welding quality evaluation apparatus

• US 6,703,585 B2
• Filed: 09/04/2002
• Issued: 03/09/2004
• Est. Priority Date: 09/20/2001
• Status: Expired due to Fees

• Current Assignee: Central Motor Wheel Company Limited (Toyota Motor Corporation)
• Original Assignee: Central Motor Wheel Company Limited (Toyota Motor Corporation)
• Inventors: Suzuki, Yukimitsu
• Primary Examiner(s): Shaw, Clifford C.
• Application Number:
  US10/064,953
• Publication Number:
  US 20030052107A1
• Time in Patent Office: 552 Days
• Field of Search: 219/130.01, 219/130.21, 219/130.32, 219/130.33, 219/137.PS
• US Class Current: 219/130.01
• CPC Class Codes: B23K 9/0953 using computing means

Abstract

An arc welding quality evaluation apparatus for consumable electrode gas shielded arc welding comprises a heat input detection means 8 for detecting heat input applied to a workpiece to be welded; a welding time detection means 11 for detecting the welding time of the workpiece; a spatter weight detection means 16 for detecting the weight of spatter produced during the welding time of the workpiece; a heat compensation means 17 for compensating for heat loss due to spatter occurring during the welding time of the workpiece; an effective heat input computation means 12 for computing effective heat input per unit welding time, based on detected values of the detection means 8 and 11, and a compensation value of the heat compensation means 17; and a weld quality assessment means 22 for comparing an output of the effective heat input computation means 12 to a reference standard value, and assessing weld quality acceptability based on the degree of separation of the computation means output from the reference standard value.

Claims

1. An arc welding quality evaluation apparatus suitable for a consumable electrode gas-shielded arc welding, wherein a welding voltage is applied between a welding wire and a workpiece to be welded, molten metal droplets from the welding wire are transferred to the workpiece, and that portion of the wire consumed by the transfer of droplets is replenished, for performing continuous arc welding, the apparatus comprising:

a heat input detection means for detecting a heat input applied to the workpiece, from the welding voltage applied thereto and a welding current supplied thereto;

a welding time detection means for detecting a workpiece welding time;

a spatter weight detection means for detecting a weight of spatter produced during the workpiece welding time;

a heat compensation means for compensating for a heat loss due to spattering during the workpiece welding time;

an effective heat input computation means for computing an effective heat input based on detected values of the heat input detection means and welding time detection means, and a heat compensation value of the heat compensation means; and

a weld quality assessment means for assessing a weld quality based on the degree of separation of an output of the effective heat input computation means from a reference standard value.

2. The arc welding quality evaluation apparatus of claim 1, wherein the weld quality assessment means computes a molten metal cross-sectional area of the workpiece, using a first conversion diagram for converting an output value of the effective heat input computation means to a workpiece molten cross-sectional area, compares the molten metal cross-sectional area to a molten reference standard value, and assesses weld quality acceptability based on the degree of separation of the molten metal cross-sectional area from the molten reference standard value.

3. The arc welding quality evaluation apparatus of claim 2, further comprising:

a supplied wire weight detection means for detecting a weight of welding wire supplied; and

a deposited metal weight computation means for computing a weight of welding wire metal deposited on the workpiece, based on values detected by the supplied wire weight detection means and spatter weight detection means;

wherein the weld quality assessment means computes a deposited metal cross-sectional area of the workpiece, using a second conversion diagram that converts an output value of the deposited metal weight computation means to a deposited metal cross-sectional area, compares the deposited metal cross-sectional area to a deposited reference standard value, and assesses weld quality acceptability based on the degree of separation of the deposited metal cross-sectional area from the deposited reference standard value;

wherein the weld quality assessment means computes an effective cross-sectional area by subtracting the deposited metal cross-sectional area from the molten metal cross-sectional area, compares the effective cross-sectional area to an area reference standard value, and assesses weld quality acceptability based on the degree of separation of the effective cross-sectional area from the area reference standard value.

4. The arc welding quality evaluation apparatus of claim 3, wherein the weld quality assessment means, the heat input, the weight of welding wire metal deposited on the workpiece, the molten metal cross-sectional area, the deposited metal cross-sectional area, and the effective cross-sectional area, are computed as average values over tho workpiece welding time, each average value is compared to a reference standard value set to the respective average value during optimum welding conditions, and weld quality acceptability is assessed based on the degree of separation of the average value from the reference standard value.

5. An arc welding quality evaluation apparatus suitable for a consumable electrode gas-shielded arc welding, wherein a welding voltage is applied between a welding wire and a workpiece to be welded, molten metal droplets from the welding wire are transferred to the workpiece, and that portion of the wire consumed by the transfer of droplets is replenished, for performing continuous arc welding, the apparatus comprising:

a supplied wire weight detection means for detecting a weight of welding wire supplied;

a spatter weight detection means for detecting a weight of spatter produced during the workpiece welding time;

a weld metal deposition efficiency computation means for computing an efficiency of deposition of welding wire metal on the workpiece, based on values detected by supplied wire weight detection means and the spatter weight detection means;

a weld quality assessment means for comparing an output value of the weld metal deposition efficiency computation means with a reference standard value, and assessing a weld quality acceptability based on the degree of separation of the computation means output value from the reference standard value.

6. An arc welding quality evaluation apparatus suitable for a consumable electrode gas-shielded arc welding, wherein a welding voltage is applied between a welding wire and a workpiece to be welded, molten metal droplets from the welding wire are transferred to the workpiece, and that portion of the wire consumed by the transfer of droplets is replenished, for performing continuous arc welding, the apparatus comprising:

a supplied wire weight detection means for detecting a weight of welding wire supplied;

a spatter weight detection means for detecting a weight of spatter produced during a workpiece welding time;

a deposited metal weight computation means for computing a weight of welding wire metal deposited on the workpiece, based on values detected by the supplied wire weight detection means and spatter weight detection means; and

a weld quality assessment means for comparing an output value of the deposited metal weight computation means with a reference standard value, and assessing a weld quality acceptability based on the degree of separation of the output value from the reference standard value.

7. The are welding quality evaluation apparatus of claim 6, wherein the weld quality assessment means computes a deposited metal cross-sectional area of the workpiece, using a second conversion diagram that converts an output value the deposited metal weight computation means to a deposited metal cross-sectional area, compares the deposited metal cross-sectional area to a deposited reference standard value, and assesses weld quality acceptability based on the degree of separation of the deposited metal cross-sectional area from the deposited reference standard value.