CN115255591A - Method for automatically detecting indentation depth of resistance spot welding - Google Patents
Method for automatically detecting indentation depth of resistance spot welding Download PDFInfo
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- CN115255591A CN115255591A CN202211078600.0A CN202211078600A CN115255591A CN 115255591 A CN115255591 A CN 115255591A CN 202211078600 A CN202211078600 A CN 202211078600A CN 115255591 A CN115255591 A CN 115255591A
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- spot welding
- position data
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K11/00—Resistance welding; Severing by resistance heating
- B23K11/36—Auxiliary equipment
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K11/00—Resistance welding; Severing by resistance heating
- B23K11/10—Spot welding; Stitch welding
- B23K11/11—Spot welding
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Abstract
The invention discloses a method for automatically detecting the depth of a resistance spot welding indentation, which comprises the following steps that a workpiece and spot welding pliers are matched to a welding position; the spot welding clamp acts and completes the pressure application of the moving electrode; recording the position of the moving electrode when the pressure of the moving electrode is applied to obtain first position data; electrifying and welding; after welding and electrifying, keeping the spot welding pliers in a pressurizing state, and recording the position of the moving electrode again to obtain second position data; and obtaining the difference value of the first position data and the second position data to obtain the indentation depth of the spot welding electrode. According to the invention, the electrode indentation depth can be simply and conveniently measured by only detecting the position data when the movable electrode is pressurized and the position data when welding is completed and in a pressurized state and utilizing the difference value of the position data and the position data, and the spot welding indentation depth can be monitored during production, so that untimely manual inspection and high cost are avoided.
Description
Technical Field
The invention relates to the technical field of spot welding indentation detection, in particular to a method for automatically detecting the depth of a resistance spot welding indentation.
Background
Currently, the primary attachment means for vehicle bodies is resistance spot welding. The depth of the resistance spot welding indentation influences the appearance and strength of the welding spot, and is an important index of spot welding quality. The depth of the resistance spot welding indentation is generally manually checked and evaluated after welding, and the detection of the depth of the spot welding indentation cannot be completed while welding production is carried out.
With the development of the technology, chinese patent application No. CN109931879A provides an on-line measuring method for the indentation depth of the surface of a welding spot based on an inter-electrode displacement signal, which forms a displacement-time curve graph by measuring the real-time change of the relative position of two electrodes in the resistance spot welding process, divides the curve into five stages according to the curve characteristics on the graph, performs curve fitting on the curve in the pressure maintaining stage after welding by using a least square method and obtains a fitting function expression, calculates and corrects the limit value of the fitting function, and subtracts the measurement value of the inter-electrode displacement in the pre-pressing stage before welding from the limit value to obtain the predicted indentation depth of the surface of the welding spot (see patent publication for details).
However, the above-mentioned indentation detection method requires real-time variation curves of the relative positions of the two electrodes, which requires monitoring the positions of the moving electrode and the static electrode, and the detection process is complicated.
Disclosure of Invention
Technical problem to be solved
The invention can solve the problems of more data to be detected and complex detection process in the conventional method for detecting the depth of the spot welding indentation.
(II) technical scheme
In order to achieve the purpose, the invention adopts the following technical scheme that the method for automatically detecting the indentation depth of the resistance spot welding specifically comprises the following steps:
s1, matching a workpiece and spot welding tongs to a welding position;
s2, the spot welding clamp acts and completes the pressure application of the moving electrode;
s3, recording the position of the moving electrode when the pressure of the moving electrode is applied to obtain first position data;
s4, electrifying and welding;
s5, after welding and electrifying, keeping the spot welding tongs in a pressurizing state, recording the position of the moving electrode again, and obtaining second position data;
and S6, obtaining a difference value of the first position data and the second position data to obtain the indentation depth of the spot welding electrode.
As a preferred technical solution of the present invention, in S1, the fitting of the workpiece and the spot welding tongs to the welding position includes any one of the following modes: moving the workpiece to a welding position; moving the spot welding tongs to a welding position; the workpiece and the spot welder are moved to the welding position simultaneously.
As a preferred technical scheme of the invention, the spot welding tongs are set to be servo spot welding tongs, the spot welding tongs comprise a tong body and a tong movable arm arranged on the tong body, the movable electrode is arranged at the lower part of the tong movable arm, and a position sensor is arranged at the side part of the tong body.
In a preferred embodiment of the present invention, in S3 and S5, the first position data is position data of the moving electrode when the position sensor directly detects that the pressure application is completed; the second position data is position data of the moving electrode when the position sensor directly detects that welding is completed and the moving electrode is in a pressure application state.
As a preferred technical solution of the present invention, in S3 and S5, the first position data is position data of the welding tongs movable arm when the position sensor detects that the pressure application is completed; the second position data is the position data of the movable arm of the welding tongs when the position sensor directly detects that welding is finished and the movable arm is in a pressure applying state.
As a preferable aspect of the present invention, the position sensors are provided in plural numbers, the first position data is an average value of detection data of the plurality of position sensors, and the second position data is an average value of detection data of the plurality of position sensors.
As a preferred embodiment of the present invention, in S2, a specific manner of applying the dynamic electrode pressure is as follows: the movable arm of the welding tongs drives the movable electrode to move, and the movable electrode is pressed on the upper part of the workpiece.
As a preferred technical solution of the present invention, in S6, after obtaining a difference between the first position data and the second position data, performing a positive calculation on the difference, and obtaining a positive value to obtain the indentation depth of the spot welding electrode.
(III) advantageous effects
The method for automatically detecting the depth of the resistance spot welding indentation provided by the invention can simply and conveniently measure the depth of the electrode indentation by only detecting the position data when the movable electrode is pressurized and the position data when the welding is finished and the electrode is in a pressurized state and utilizing the difference value of the position data and the position data, and can monitor the depth of the spot welding indentation while producing, thereby avoiding untimely manual inspection and high cost.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.
FIG. 1 is a schematic block flow diagram of the present invention;
FIG. 2 is a schematic mechanical diagram of the body portion of the soldering tweezers of the present invention;
FIG. 3 is a schematic diagram showing the movement of the movable electrode in example 1 of the present invention;
FIG. 4 is a schematic diagram showing the movement of the moving electrode in example 2 of the present invention;
fig. 5 is a schematic diagram of the moving electrode movement in embodiment 3 of the present invention.
In the figure: 1. a soldering turret body; 2. a movable arm of the welding tongs; 3. and a moving electrode.
The implementation, functional features and advantages of the objects of the present invention will be further explained with reference to the accompanying drawings.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.
Thus, the following detailed description of the embodiments of the present invention, as presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.
It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.
In the description of the present invention, it is to be understood that the terms "longitudinal", "upper", "lower", "left", "right", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, are used only for convenience in describing the present invention and for simplicity in description, and do not indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and thus, are not to be construed as limiting the present invention.
Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.
Example 1
As shown in fig. 1, fig. 2 and fig. 3, a method for automatically detecting the indentation depth of resistance spot welding specifically comprises the following steps:
s1, moving a workpiece to a welding position;
s2, the spot welding tongs act and complete the application of the movable electrode pressure, in the embodiment, the spot welding tongs are set as servo spot welding tongs, the spot welding tongs comprise a tong body 1 and a tong movable arm 2 arranged on the tong body 1, the movable electrode 3 is arranged on the lower part of the tong movable arm 2, a position sensor is arranged on the side part of the tong body 1, and when the spot welding tongs are used, the tong movable arm drives the movable electrode to move to press the movable electrode on the upper part of a workpiece; it should be understood that, because the servo spot welding clamp is adopted, and the servo motor spot welding clamp is provided with the displacement sensor, the displacement sensor can be used for displacement measurement by adopting the displacement sensor carried by the servo motor spot welding clamp, so that the hardware investment is reduced.
S3, recording the position of the moving electrode when the pressure of the moving electrode is applied to obtain first position data, wherein the time at this moment is T0, the position of the moving electrode is P0, for example, P0=50um, and when the position data is specifically set, the first position data is the position data of the moving electrode when the pressure application is directly detected by a position sensor;
s4, electrifying and welding;
s5, after welding and electrifying, keeping the spot welding clamp in a pressurizing state, recording the position of the moving electrode again, and obtaining second position data, wherein the second position data is the position data of the moving electrode when the position sensor directly detects that welding is finished and the moving electrode is in a pressure applying state during specific setting;
and S6, obtaining a difference value between the first position data and the second position data to obtain the indentation depth of the spot-welding movable electrode, for example, at the time T1 in FIG. 3, the position corresponding to the movable electrode is P1, recording the position of the movable electrode again (P1, for example, P1=200 um), comparing the difference value delta P = P0-P1= -150um of the positions of the movable electrode twice, and taking the positive value as the indentation depth of the spot-welding electrode.
In this embodiment, the position sensor is provided with a plurality of, and first position data is the average value of a plurality of position sensor detection data, and second position data is the average value of a plurality of position sensor detection data to obtain more accurate position data, it should be understood that, the data that position sensor detected, only need monitor the displacement in the indentation depth direction, when selecting for use position sensor to detect is the three-dimensional coordinate, need get rid of in advance with indentation depth direction irrelevant two other coordinate numerical value.
Example 2
As shown in fig. 1, 2 and 4, a method for automatically detecting the depth of a resistance spot welding indentation specifically comprises the following steps:
s1, moving a spot welding clamp to a welding position;
s2, the spot welding tongs act and complete the application of the movable electrode pressure, in the embodiment, the spot welding tongs are set as servo spot welding tongs, the spot welding tongs comprise a tong body 1 and a tong movable arm 2 arranged on the tong body 1, the movable electrode 3 is arranged on the lower part of the tong movable arm 2, a position sensor is arranged on the side part of the tong body 1, and when the spot welding tongs are used, the tong movable arm drives the movable electrode to move to press the movable electrode on the upper part of a workpiece;
s3, recording the position of the movable electrode when the pressure of the movable electrode is applied, and obtaining first position data, wherein the time at the time is T0, the position of the movable electrode is P0, for example, P0=30um, and when the position data is specifically set, the first position data is the position data of the movable arm of the welding clamp when the position sensor detects that the pressure is applied;
s4, electrifying and welding;
s5, after welding and electrifying, keeping the spot welding tongs in a pressurizing state, recording the position of the moving electrode again, and obtaining second position data, wherein the second position data is the position data of the moving arm of the spot welding tongs when the position sensor directly detects that welding is completed and the spot welding tongs are in a pressure applying state during specific setting;
and S6, obtaining a difference value between the first position data and the second position data, performing positive calculation on the difference value, obtaining a positive value to obtain the indentation depth of the spot welding movable electrode, for example, at the time T1 in FIG. 4, the position corresponding to the movable electrode is P1, recording the position of the movable electrode (P1, for example, P1=170 um) again, comparing the difference value delta P = P0-P1= -140um of the positions of the movable electrode twice, and obtaining the indentation depth of the spot welding electrode after the positive calculation.
In this embodiment, the position sensor is provided with a plurality of, and first position data is the average value of a plurality of position sensor detection data, and second position data is the average value of a plurality of position sensor detection data to obtain more accurate position data, it should be understood that, the data that position sensor detected, only need monitor the displacement in the indentation depth direction, when selecting for use position sensor to detect is the three-dimensional coordinate, need get rid of in advance with indentation depth direction irrelevant two other coordinate numerical value.
Example 3
As shown in fig. 1, fig. 2 and fig. 5, a method for automatically detecting the indentation depth of resistance spot welding specifically comprises the following steps:
s1, simultaneously moving a workpiece and a spot welding tongs to a welding position;
s2, the spot welding tongs act and complete the application of the movable electrode pressure, in the embodiment, the spot welding tongs are set as servo spot welding tongs, the spot welding tongs comprise a tong body 1 and a tong movable arm 2 arranged on the tong body 1, the movable electrode 3 is arranged on the lower part of the tong movable arm 2, a position sensor is arranged on the side part of the tong body 1, and when the spot welding tongs are used, the tong movable arm drives the movable electrode to move to press the movable electrode on the upper part of a workpiece;
s3, recording the position of the moving electrode when the pressure of the moving electrode is applied, and obtaining first position data, wherein the time at the time is T0, the position of the moving electrode is P0, for example, P0=70um, and when the position data is specifically set, the first position data is the position data of the moving electrode when the pressure application is directly detected by a position sensor;
s4, electrifying and welding;
s5, after welding and electrifying, keeping the spot welding pliers in a pressurizing state, recording the position of the moving electrode again, and obtaining second position data, wherein the second position data is the position data of the moving electrode when the position sensor directly detects that welding is completed and the spot welding pliers are in a pressure applying state during specific setting;
and S6, obtaining a difference value between the first position data and the second position data, performing positive calculation on the difference value, obtaining a positive numerical value to obtain the indentation depth of the spot welding movable electrode, for example, at the time T1 in FIG. 5, the position corresponding to the movable electrode is P1, recording the position of the movable electrode (P1, for example, P1=210 um) again, comparing the difference value delta P = P0-P1= -140um of the two times of the positions of the movable electrode, and obtaining the indentation depth of the spot welding electrode after the positive calculation.
In this embodiment, the position sensor is provided with a plurality of position sensors, the first position data is an average value of the detection data of the plurality of position sensors, and the second position data is an average value of the detection data of the plurality of position sensors, so as to obtain more accurate position data.
In conclusion, the electrode indentation depth can be simply and conveniently measured by detecting the position data when the movable electrode is pressurized and the position data when welding is completed and the movable electrode is in a pressurized state and utilizing the difference value of the position data and the position data, the spot welding indentation depth can be monitored during production, and untimely manual inspection and high cost are avoided.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (8)
1. A method for automatically detecting the indentation depth of resistance spot welding is characterized in that: the method specifically comprises the following steps:
s1, matching a workpiece and spot welding pliers to a welding position;
s2, the spot welding clamp acts and completes the pressure application of the moving electrode;
s3, recording the position of the moving electrode when the pressure of the moving electrode is applied to obtain first position data;
s4, electrifying and welding;
s5, after welding and electrifying, keeping the spot welding pliers in a pressurizing state, recording the position of the moving electrode again, and obtaining second position data;
and S6, obtaining a difference value of the first position data and the second position data to obtain the indentation depth of the spot welding electrode.
2. The method for automatically detecting the indentation depth of resistance spot welding according to claim 1, wherein the step S1 of fitting the workpiece and the spot welding tongs to the welding position comprises any one of the following manners:
moving the workpiece to a welding position;
the spot welding tongs are moved to the welding position;
the workpiece and the spot welder are moved to the welding position simultaneously.
3. The method for automatically detecting the indentation depth of resistance spot welding according to claim 1, characterized in that the spot welding tongs are configured as servo spot welding tongs, the spot welding tongs comprise a tongs body (1), a tongs movable arm (2) arranged on the tongs body (1), the movable electrode (3) is installed on the lower part of the tongs movable arm (2), and a position sensor is installed on the side part of the tongs body (1).
4. The method for automatically detecting the indentation depth of resistance spot welding according to claim 3, wherein in the steps S3 and S5, the first position data is the position data of the moving electrode when the position sensor directly detects the pressure application is completed; the second position data is position data of the moving electrode when the position sensor directly detects that welding is completed and the moving electrode is in a pressure application state.
5. The method for automatically detecting the indentation depth of resistance spot welding according to claim 4, wherein in the steps S3 and S5, the first position data is the position data of the welding clamp arm when the position sensor detects that the pressure application is completed; the second position data is the position data of the movable arm of the welding tongs when the position sensor directly detects that welding is finished and the movable arm is in a pressure applying state.
6. The method for automatically detecting the indentation depth of resistance spot welding according to claim 4, wherein: the position sensors are provided with a plurality of position sensors, the first position data are average values of the detection data of the position sensors, and the second position data are average values of the detection data of the position sensors.
7. The method for automatically detecting the indentation depth of resistance spot welding according to claim 3, wherein in the step S2, the electrode moving pressure is applied in a specific manner that: the movable arm of the welding tongs drives the movable electrode to move, and the movable electrode is pressed on the upper part of the workpiece.
8. The method according to claim 1, wherein in step S6, after obtaining the difference between the first position data and the second position data, the difference is calculated by taking the positive value, and the spot welding electrode indentation depth is obtained by taking the positive value.
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| CN202211078600.0A CN115255591A (en) | 2022-09-05 | 2022-09-05 | Method for automatically detecting indentation depth of resistance spot welding |
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| CN202211078600.0A CN115255591A (en) | 2022-09-05 | 2022-09-05 | Method for automatically detecting indentation depth of resistance spot welding |
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4005307A (en) * | 1974-09-17 | 1977-01-25 | Toyota Jidosha Kogyo Kabushiki Kaisha | Method and apparatus for judging quality of spot weld |
| US5558785A (en) * | 1994-04-08 | 1996-09-24 | Eaton Corporation | Inter-electrode displacement monitoring and control |
| CN1864905A (en) * | 2006-06-22 | 2006-11-22 | 上海交通大学 | Electrode dressing on-line distinguishing method based on spot-welding of servo torch |
| US20080128394A1 (en) * | 2006-12-01 | 2008-06-05 | Gm Global Technology Operations, Inc. | Monitoring and repair method for adhesive bonding |
| US20110253681A1 (en) * | 2010-04-07 | 2011-10-20 | Pei-Chung Wang | Method of controlling an indentation depth of an electrode into a metal substrate during welding |
| CN103658956A (en) * | 2012-09-26 | 2014-03-26 | 中国石油大学(华东) | Online judging method of quality of welding points welded by servo welding gun in resistance spot welding mode |
-
2022
- 2022-09-05 CN CN202211078600.0A patent/CN115255591A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4005307A (en) * | 1974-09-17 | 1977-01-25 | Toyota Jidosha Kogyo Kabushiki Kaisha | Method and apparatus for judging quality of spot weld |
| US5558785A (en) * | 1994-04-08 | 1996-09-24 | Eaton Corporation | Inter-electrode displacement monitoring and control |
| CN1864905A (en) * | 2006-06-22 | 2006-11-22 | 上海交通大学 | Electrode dressing on-line distinguishing method based on spot-welding of servo torch |
| US20080128394A1 (en) * | 2006-12-01 | 2008-06-05 | Gm Global Technology Operations, Inc. | Monitoring and repair method for adhesive bonding |
| US20110253681A1 (en) * | 2010-04-07 | 2011-10-20 | Pei-Chung Wang | Method of controlling an indentation depth of an electrode into a metal substrate during welding |
| CN103658956A (en) * | 2012-09-26 | 2014-03-26 | 中国石油大学(华东) | Online judging method of quality of welding points welded by servo welding gun in resistance spot welding mode |
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