WO2015194748A1

WO2015194748A1 - Device for checking spot welding electrode tip polishing

Info

Publication number: WO2015194748A1
Application number: PCT/KR2015/003510
Authority: WO
Inventors: 김종식; 김명진; 홍기복; 신철희
Original assignee: 주식회사 휴비스
Priority date: 2014-06-20
Filing date: 2015-04-08
Publication date: 2015-12-23
Also published as: KR20150145597A

Abstract

The present invention relates to a device for checking spot welding electrode tip polishing, which inspects a polishing state of an electrode tip attachably/detachably provided to a spot welding gun and, more specifically, to a device for checking spot welding electrode tip polishing, which is configured to allow: both surfaces of a pressure-sensitive sheet to be pressed with one pair of electrode tips similarly to when spot welding on two overlapping sheets of metal plates is performed; a state of an electrode tip to be inspected by reading an image of a pressure mark shown as a developed color of a portion pressed by the electrode tip; the electrode tip to be inspected in real-time by being provided to a product manufacturing process line having a spot welding gun, thereby: signaling an alarm for polishing, replacement or alignment of an electrode tip according to an inspection result; preserving pressure-sensitive sheets and images as a record so as to use the record as base data for guaranteeing the quality of a welding state; and providing a proper polishing period and a proper replacement time point of an electrode tip so as to be well-prepared for managing a process line.

Description

Spot welding electrode tip polishing confirmation device

The present invention relates to a spot welding electrode tip polishing confirmation device for inspecting the polishing state of the electrode tip detachably installed in the spot welding gun, and more specifically, a pair of two overlapping metal plates similar to spot welding It is possible to press both sides of the pressure-sensitive paper with the electrode tip, and to check the state of the electrode tip by reading the indentation that appears in the color of the pressed part on the electrode tip, and to inspect the state of the electrode tip. The tip can be inspected to alarm for grinding, replacing or aligning the electrode tip according to the test result, and to store the pressure-sensitive paper and images as a record and to use it as a basis for quality assurance of the welding state. Pre-spot welding to ensure the management of the process line by providing the team with the right grinding cycles and the right replacement points It relates to the grinding tip verify.

Spot welding is to overlap two panels by setting the spots to be spot welded, and by putting a pair of electrodes on each side of the spots, applying local high current between electrodes and applying pressure to both electrodes. It is the welding which melts and joins a site | part. Such spot welding is widely used in automobile body lines and production sites of various products because the welding operation is simple and the panel deformation due to rust or heat does not easily occur.

FIG. 1 is a cross-sectional view (FIG. 1A) in which two electrodes face each other, and a cross-sectional view (FIG. 1B) after spot welding by pressurizing a current while flowing an electrode therebetween.

First, referring to Figure 1a, the welding gun 10 is provided with shank (11a, 11b) that can be matched with the center axis, facing each other and adjustable spacing, the electrode tip (20a, 11b) at the end of each shank (11a, 11b) 20b) is detachably mounted to constitute a pair of electrodes.

The tip faces 21 of the

electrode tips

20a and 20b have a circular shape, and an arc face 22 is formed starting from the tip face 21 and gradually increasing in diameter toward the outer periphery. The diameter of 21 is polished to a preset value, and the arc surface 22 is also polished to form a curved surface with a preset radius. In general, a wear reference groove 23 is formed along the periphery of the outer circumferential surface to indicate the minimum length for functioning as an electrode tip when the

electrode tips

20a and 20b are repeatedly polished and used.

The

electrode tips

20a and 20b detachably mounted to the

shanks

11a and 11b are reused by polishing with a tip dresser when the tip surface 21 wears or becomes contaminated with an oxide film or the like according to the number of spot welding. If it is repeatedly polished and can no longer perform the function of the electrode tip, it is replaced.

In the case of spot welding, as shown in FIG. 1A, the front end surface 21 of the

electrode tips

20a and 20b having the central axis coincident with both sides of the overlapping

panels

3a and 3b with the overlapping

panels

3a and 3b interposed therebetween. ) And then a current flows through the distal end surface 21 of the

electrode tips

20a and 20b, so that a portion where the current flows locally by the

electrode tips

20a and 20b in the contact surfaces of the

panels

3a and 3b. Melt by contact resistance heat, and at this time, it is pressed by the electrode tips (20a, 20b). Accordingly, referring to FIG. 1B, the spot welded portion is a panel 3a which is pressed by the nugget 4a and nugget and the

electrode tips

20a and 20b, which are spot welded to the contact surfaces of the

panels

3a and 3b. , 3b) shows the concave marks 4b on the surface.

Spot welding made in this way can ensure the welding quality when the welding current, the energization time and the pressing force, which are the three major conditions of welding, are properly maintained, and the electrode tip is kept in good condition, but otherwise the welding condition may be poor. have.

Types of welding failure include intermediate blown out of molten metal from the contact surface between the

panels

3a and 3b, blown out surface of molten metal from the panel surface pressed by the

electrode tips

20a and 20b, and recessed marks 4b. ) Narrowness of excessively small size, penetration nonuniformity of pentration (4c), nonuniformity of penetration, nugget deformation in which nugget 4a is not smooth like a goggle and deformed, position where nugget 4a is to be formed Blow holes in which air bubbles are generated, nugget cracks in which cracks occur in the nugget 4a, nugget deficiency in which the nugget 4a is formed too small, and excessive penetration in which the nugget 4a is excessively large, etc. have.

Among these kinds of welding defects, intermediary blowing, surface blowing, concave trace narrowing, penetration nonuniformity, nugget deformation, and blow hole may occur depending on the state of the electrode tip even if the three conditions of welding are properly matched.

The state of the electrode tip includes the size of the tip diameter of the electrode tip, the alignment of the electrode tip, the angle of the electrode tip, the current length due to the repeated polishing of the electrode tip, the tip deformation of the electrode tip or the degree of contamination.

As a conventional technique for inspecting and determining the state of the electrode tip, Patent Nos. 10-1360301 and 10-1326033 are images taken by photographing an electrode tip with a camera or an optical sensor.

However, the prior art is not a test of the electrode tip in the situation of pressing the plate to be welded, but an image of a pair of electrode tips spaced apart from each other, the inspection is different from the electrode tip state when the actual spot welding You can get the result. In other words, the actual welding quality can be ensured only by inspecting the state when pressing both sides of the plate simultaneously with a pair of electrode tips, but the prior art may have an error due to an error in image reading.

On the other hand, decompression paper is useful as a means for measuring the contact state and the pressing force, but it was not used to inspect and determine the state of the electrode tip in real time at the product production site equipped with a welding robot equipped with a spot welding welding gun. .

Therefore, there is a need for a device that can be installed near the welding robot on the product production site to inspect the welding tip state of the welding gun in real time using a pressure-sensitive paper in real time.

[Preceding technical literature]

[Patent Documents]

(Patent Document 1) KR 10-1360301 B1 2014.02.03.

(Patent Document 2) KR 10-1326033 B1 2013.10.15.

Accordingly, it is an object of the present invention to provide a spot welding electrode tip polishing confirmation apparatus capable of inspecting a welding tip in a state close to the spot welding with an electrode tip, and inspecting the welding tip in real time at a product production site.

In order to achieve the above object, the present invention is fixed to a spot welding welding gun mounted on a welding robot to press a pair of electrode tips for point resistance welding while pressing both sides of the spot to be welded with the welding material therebetween to the tip surface. A spot welding electrode tip polishing confirmation apparatus for inspecting, comprising: a recorder (200) in which a pair of electrode tips pressurizes both sides of a pressure sensitive paper to form an indentation while the pressure sensitive paper wound on the first reel is unwound and wound on the second reel; A vision sensor 300 for photographing a portion where an indentation is formed before the pressure-sensitive paper is wound on the second reel; A controller 100 extracting an indentation image from the image photographed by the vision sensor and determining a state of an electrode tip from the indentation image; Characterized in that configured to include.

The recorder 200 includes a pressure-sensitive paper loading unit 240 for guiding the pressure-sensitive paper so that the pressure-sensitive paper released from the first reel passes through the pressure developing space exposing both sides of the pressure-sensitive paper and then wound on the second reel. It is characterized in that the indentation is formed by pressing both sides of the pressure-sensitive paper with a pair of electrode tips in the space.

The recorder 200 is configured to be parallel to the axial direction of the first reel and the second reel, the pressure-sensitive paper loading unit 240 is provided to protrude to the outside of the recorder 200, decompression released from the first reel The width direction of the paper is inclined at a predetermined angle to pass the pressure-sensitive paper in the tilted state, and thereafter, the width direction of the pressure-sensitive paper is inversely parallel to the axial direction of the second reel to wind the pressure-sensitive paper on the second reel. It is characterized in that to guide the decompression paper.

The predetermined angle is characterized in that 90 °.

The pressurizing developing space is provided with two sheets of flexible insulating paper covering both sides of the pressure-sensitive paper, pressurized by the pair of electrode tips while wrapped in two sheets of flexible insulating paper, and the pressure-sensitive paper passed between the two insulating papers is In order to capture the image by the vision sensor 300, a photographing space following the pressing development space is provided.

A cartridge including a pressure-sensitive paper wound around the first reel, the second reel, and the first reel, and the recorder 200 is installed in the mounting groove into which the cartridge is inserted, and the first reel and the second reel. And a motor for rotating the reel disk to be inserted into the reel disk, characterized in that the cartridge is replaceable.

The pressure-sensitive paper loading unit 240 is characterized in that it is configured integrally with the cartridge.

The controller 100 is linked to the welding robot to form an indentation in the pressure-sensitive paper of the recorder 200 at the time of rest of the welding robot welding process, so that the pressure-sensitive paper is wound on the second reel with a predetermined length every time the indentation is formed. The recorder is controlled, and the wear state inspection of the electrode tip using the diameter of the indentation, the alignment inspection of the electric tip using the shape of the indentation, and the inclination of the electrode tip are performed.

The present invention configured as described above has a structure that can pressurize the pressure-sensitive paper with the electrode tip of the spot welding gun while supplying the pressure-sensitive paper continuously, it is installed on the product production site where the actual welding process is performed, the state of the electrode tip in real time It can be inspected and discriminated, and the inspection that reflects the welding state of the plate more accurately because it checks and discriminates the state of the electrode tip by indentation by pressurizing the pressure-sensitive paper in the same way as pressurizing the plate with a pair of electrode tips to weld the plate. A determination result can be obtained.

In addition, the present invention by storing the pressure-sensitive paper and the image obtained by photographing the indentation formed by indentation, it is possible to confirm the welding point made at any point in which welding gun of any process was welded to the electrode tip of which state, quality control of the recording And quality assurance materials.

1 is a sectional view of a welded portion before spot welding and after spot welding.

2 is a block diagram of a spot welding electrode tip polishing confirmation device according to an embodiment of the present invention.

3 is a partial cross-sectional view of the pressure-sensitive paper loading unit 240.

4 is a perspective view of the recorder 200 with the replaceable cartridge 230 removed.

5 is a perspective view of the cartridge 230 and the pressure-sensitive paper loading unit 240.

Figure 6 is an installation example of the spot welding electrode tip polishing confirmation device according to an embodiment of the present invention.

FIG. 7 is a view showing that the lead-out part 241 and the recovery part 242 of the pressure-sensitive paper loading part may be configured as

rollers

246a, 246b, 247a, and 247b in the embodiment of the present invention.

Hereinafter, with reference to the accompanying drawings, preferred embodiments of the present invention will be described to be easily carried out by those of ordinary skill in the art. In the accompanying drawings, it is to be noted that the same reference numerals as shown in the configuration or action, the same reference numerals are used as much as possible when indicating the same configuration or action in the other drawings. In the following description of the present invention, detailed descriptions of well-known functions or well-known structures will be omitted if they are determined to unnecessarily obscure the subject matter of the present invention.

2 is a block diagram of a spot welding electrode tip polishing confirmation device according to an embodiment of the present invention, Figure 3 is a partial cross-sectional view of the pressure-sensitive paper loading unit 240, Figure 4 is a state in which the replaceable cartridge 230 is separated 5 is a perspective view of the recorder 200, and FIG. 5 is a perspective view of the integrated cartridge 230 and the pressure-sensitive paper loading unit 240. As shown in FIG. In FIG. 4, the cartridge 230 and the pressure-sensitive paper loading unit 240 are shown in perspective, and the motor 220 mounted inside the recorder 200 is shown in perspective. 5 also shows a perspective view of the cartridge 230 and the pressure-sensitive paper loading unit 240.

6 is an exemplary view illustrating the installation of a spot welding electrode tip polishing confirmation apparatus according to an exemplary embodiment of the present invention.

First, referring to FIG. 6, the spot welding electrode tip polishing confirmation apparatus according to the embodiment of the present invention is installed in a process line in which a welding robot 1 equipped with a spot welding welding gun 2 is used, and thus, a welding gun ( The state of the

electrode tips

20a and 20b fixed to 2) is inspected in real time. If it is determined that polishing of the electrode tip is necessary, the welding robot 1 causes the tip dresser 30 provided in the vicinity to polish the end faces of the

electrode tips

20a and 20b, and the

electrode tips

20a and 20b. If it is necessary to replace the alarm.

The spot welding electrode tip polishing confirmation apparatus according to an embodiment of the present invention for this purpose will be described with reference to FIGS. 1 to 5.

1 to 5, the spot welding electrode tip polishing confirmation apparatus according to the embodiment of the present invention applies a pressure mark 231a by pressing the

electrode tips

20a and 20b to the pressure-sensitive paper 231. It is configured to include a recorder 200 configured to record, the vision sensor 300 for photographing the indentation 231a, and the controller 100 for inspecting and determining the state of the electrode tip from the indentation image. same.

The recorder 200 includes a first reel 232 wound around the pressure-sensitive paper 231 and a second reel 233 provided to rewind the pressure-sensitive paper 231 wound on the first reel 232. A cartridge 230 detachable from the recorder 200 and replaceable; A motor 220 for rotating the second reel 233 to release the pressure-sensitive paper 231 wound on the first reel 232 and to wind the second reel 233 to the second reel 233; The pressure-sensitive paper 231 is guided so that the pressure-sensitive paper 231 unwound from the first reel 232 of the cartridge 230 is wound on the second reel 233, but the pair of

electrode tips

20a and 20b are decompressed during the guide. A photographing space provided for photographing the press development space 244 provided to press the both sides with the paper 231 interposed therebetween to form the indentation 231 a and the indentation 231 a formed in the press development space 244 ( Pressure-sensitive paper loading unit 240 having a 245; It is configured to include.

Here, the pressure-sensitive paper 231 is a paper that develops color under pressure when the pressure is applied. For example, a very small capsule containing paint is applied to a paper, and the capsule under pressure is blown out to make the paint leak. Is made. For example, commercially available products are sold by Fujifilm Co., Ltd. under the trade name "PRESCALE", which is used for pressure measurement because the concentration of the color varies depending on the size of the pressure. In the embodiment of the present invention, the pressure-sensitive paper is used, which is colored under pressure, but has different concentrations of colors.

In the embodiment of the present invention, the pressure-sensitive paper loading unit 240 is integrally formed with the cartridge 230 and replaced with the cartridge 230.

Specifically, the cartridge 230 is provided with an inner space surrounded by sidewalls along the edges of the top and bottom plates spaced like a cassette that wraps a typical audio tape or video tape, and the rotation axis directions are parallel to each other. The first reel 232 and the second reel 233 penetrating are supported on the upper plate and the lower plate to be rotatable, and the first reel 232 and the second reel 233 are formed in a hollow ring shape. The first reel 232 and the second reel 233 can be rotated from the outside, respectively. In addition, one side of the cartridge 230 is provided with one end of the outlet 234 and the other end of the recovery port 235 for passing the pressure-sensitive paper. In addition, the pressure-sensitive paper 231 is wound around the first reel 232 is received in the cartridge 230, the end of the pressure-sensitive paper 231 passes through the outlet 234 to the pressure-sensitive paper loading unit 240 After being guided, it is fixed to the outer edge of the second reel 233 through the recovery port 235.

Accordingly, when the second reel 233 is rotated, the pressure-sensitive paper 231 wound on the first reel 232 is released, guided to the pressure-sensitive paper loading unit 240, and then wound on the second reel 233.

In this case, the pressure-sensitive paper loading unit 240 is provided to protrude to the outside of the side wall formed with the outlet 234 and the recovery port 235, starting at the outlet 234 and continues to the recovery port 235 ' A pressure developing space 244 which forms a 유도 'shaped induction path, and exposes both sides of the pressure sensitive paper in the middle of the induction path to pressurize both sides of the pressure sensitive paper with a pair of electrode tips to form an indentation 231a; An image capturing space 245 is provided in which at least one surface of the indentation 231a is formed on both sides of the paper so that the indentation 231a can be photographed by the vision sensor 300.

In detail, the pressure-sensitive paper loading unit 240 forms an induction path in a '┏' shape and forms an induction path in a '┓' shape and an outlet part 241 connected to the outlet opening 234 and the recovery port. It is composed of a recovery unit 242 connected to 235, the withdrawal unit 241 and the recovery unit 242 is configured to be separated from each other, between the end of the withdrawal unit 241 and the end of the recovery unit 242 Allow space to form. In this case, the formed space provides a pressing developing space 244 that extends to the end of the lead-out unit 241 and a photographing space 245 that extends from the pressing developing space 244 to the end of the collecting unit 242. In addition, an imaginary line between the end of the lead portion 241 and the end of the recovery portion 242 is parallel to the sidewall of the cartridge in which the outlet 234 and the recovery port 235 are formed.

According to an embodiment of the present invention, the induction path bent in the '┏' shape of the lead-out portion 241 has a width slightly larger than the width of the pressure-sensitive paper 231 to pass through the pressure-sensitive paper 231, Is formed as a passage having a slightly larger height, the width direction is formed so as to be gently inclined at a predetermined angle in the portion bent by the letter '┏'. Accordingly, the width direction of the pressure-sensitive paper 231 released from the first reel 232 is gently rotated so as to be inclined at the predetermined angle while passing through the withdrawal portion 241.

In addition, the passage having a width slightly larger than the width of the pressure-sensitive paper 231 and a height slightly larger than the thickness of the pressure-sensitive paper in order to allow the pressure-sensitive paper 231 to pass through the induction road bent in a '┓' shape of the recovery part 242. Wherein the inlet of the end is formed to face each other with the same width direction as the end inlet of the lead-out portion 241, so that the width direction is parallel to the axial direction of the second reel in the portion bent by '┏' It has a shape inclined gently in the direction opposite to the inclination direction of the lead portion 241. Accordingly, the decompression paper released from the first reel is pulled out at an inlet of the end of the lead portion 241 in a state in which the width direction is inclined at the predetermined angle to sequentially advance the pressure developing space 244 and the imaging space 245. After passing through, the width direction is rotated by the recovery part 242 to be parallel to the axial direction of the second reel, so that it is wound around the second reel 233 without being twisted.

In this case, the predetermined angle may be larger than 0 ° and not exceeding 90 ° in the predetermined rotation direction regardless of which direction the pressure sensitive paper width direction is rotated. However, in order to prevent the welding gun from being caught by the recorder 200 when pressing the pressure-sensitive paper with the electrode tip, the predetermined angle may be made as large as possible within the range not exceeding 90 °.

In a specific embodiment of the present invention, as shown in the accompanying drawings, the predetermined angle is set to 90 °.

By forming the withdrawal part 241 and the recovery part 242 in this way, the width direction of the pressure-sensitive paper passing through the pressurization developing space 244 and the imaging space 245 formed between the withdrawal part 241 and the recovery part 242. Is a direction toward the cartridge 230, and thus, the cartridge 230 or the recorder 200 is pressed when the pressure-sensitive paper 231 is pressed by the pair of

electrode tips

20a and 20b in the pressure developing space 244. Do not get caught in.

However, since the

electrode tips

20a and 20b receive heat when performing spot welding, when the

electrode tips

20a and 20b directly contact the pressure-sensitive paper 231, the

electrode tips

20a and 20b are decompressed by the heat of the electrode tips 20a and 20b. 231 may be damaged.

Thus, in the embodiment of the present invention, in order to prevent the heat of the

electrode tips

20a and 20b from being transferred to the pressure-sensitive paper 231, the upper and lower surfaces of the pressure-sensitive paper 231 passing through the pressure developing space 244 are 2 The sheet is covered with flexible insulating paper 243. Accordingly, the pressure-sensitive paper 231 passes between the two flexible insulating papers 243 in the pressure developing space 244, and the pressure-sensitive paper 231 passes through the pair of electrode tips in the pressure developing space 244. When pressurizing the pressure-sensitive paper 231 in a state wrapped in the insulating paper 243 to be pressed. Thereafter, the pressure-sensitive paper 231 passes through the photographing space 245, enters the recovery part 242, and is wound around the second reel of the cartridge 230.

Here, the heat insulating paper 243 is formed of a flexible plate having a heat insulating performance, such as silicone rubber, fluorine rubber or silica rubber, so that only the portion pressed against the tip end surface of the electrode tip is pressed and pressurized the pressure-sensitive paper 231. Let's do it. In the embodiment of the present invention, in order to prevent the heat insulating paper 243 from sagging, both widthwise ends of the two heat insulating paper 243 are connected to each other, so that a passage substantially connected to the end of the lead portion 241 is formed. It was.

As such, the cartridge 230 formed integrally with the pressure-sensitive paper loading unit 240 is mounted to the recorder 200 so that the cartridge 230 can be replaced. For this purpose, the cartridge 230 is inserted into and mounted on a portion of the upper surface of the recorder 200. The cartridge mounting groove 210 is formed, and one side of the recorder 200 is cut toward the cartridge mounting groove 210, so that the cartridge 230 is inserted into the cartridge mounting groove 210 to integrate the pressure-sensitive paper. The loading unit 240 is exposed to the outside of the recorder 200 through the cut portion of the side.

In addition, the mounting groove 210 is provided with

reel disks

211 and 212 inserted into the inner hollow of the first reel 232 and the second reel 233 of the cartridge 230, and the first reel 232. The reel disk 211 inserted into the free reel is rotated, and the reel disk 212 inserted into the second reel 233 is rotated by the motor 220.

Here, the driving of the motor 220 provided in the recorder 200 is controlled by the controller 100.

The vision sensor 300 photographs the photographing space 245, and a pair of electrode tips 20a approaching the decompression paper 231 to pressurize the decompression paper 231 in the pressure developing space 244. , The front end surface 21 and the outer peripheral surface of the camera 20b is provided to photograph. In the embodiment of the present invention, since one camera 310 is used, the capturing space 245, the front end surface 21 and the outer circumferential surface of the

electrode tips

20a and 20b should be within the shooting range of the camera 310. The one electrode tip 20b of the pair of

electrode tips

20a and 20b is out of the photographing range of the camera 310, so that any one electrode tip 20b is connected to the camera through the reflector 320. 310 to be photographed.

Here, in the photographing space 245, the pressure-sensitive paper 231 having the indentation 231a formed by the

electrode tips

20a and 20b in the pressing and developing space 244 is wound on the second reel through the recovery part 242. Since the space is completely exposed, the indentation 231a formed on the pressure-sensitive paper 231 may be photographed.

In the embodiment of the present invention, one camera is used, but a camera for photographing the front end surfaces 21 and the outer circumferential surfaces of the

electrode tips

20a and 20b may be provided separately from the camera for photographing the photographing space 245. .

The controller 100 is linked to the operation of the welding robot 1 is equipped with electrode tips (20a, 20b) to control the driving of the motor 220 of the recorder 200 and the photographing operation of the vision sensor 300 By using the image captured by the vision sensor 300 to check and determine the state of the electrode tip (20a, 20b), to alarm according to the test result, to make a database of the image to use as a basis material, Provide statistics on polishing and replacement cycles.

To this end, the controller 100 is a communication module 110 for transmitting a signal to the welding robot 1, a drive unit 120 for transmitting an operation command to the motor 220 and the vision sensor 300, and various Display unit 130 for outputting information to the screen, an alarm unit 131 consisting of a lamp or a speaker to alarm, a data storage unit 140 to provide a data storage space, and the image captured by the vision sensor 300 The image processing unit 150 extracts the image of the indentation 231a, the tip surface images of the

electrode tips

20a and 20b, and the side images of the

electrode tips

20a and 20b from the image, and the state of the electrode tip from the extracted image. And a statistical calculation unit 170 for storing the inspection result and the video image in the data storage unit 140 and calculating statistical data from the stored data.

The communication module 110 is to allow the operation of the controller 100 to be interlocked with the welding robot 1, and the welding robot 1 at the time when the welding robot 1 is idle during the welding process, that is, when it is waiting without welding. Receive a pulse signal, for example. The pulse signal may include a first pulse signal at the time when the welding robot 1 moves the welding gun to the pressure developing space 244 and a second pulse signal after pressing the pressure-sensitive paper with the electrode tip mounted on the welding gun. have.

Here, the welding robot 1 is tilted to simultaneously press both sides of the pressure-sensitive paper with the pair of

electrode tips

20a and 20b by moving the welding gun 10 to the pressure developing space 244 at the time of rest. That is, the welding robot 1 is programmatically set so as to pressurize the pressure-sensitive paper at the resting time, using the press-development space 244 as the RBI, similarly to when welding the welded object.

Thus, the operation when receiving a pulse signal from the welding robot 1 will be described as follows.

First, upon receiving the first pulse signal, the driving unit 120 operates the vision sensor 300 to perform a photographing operation. Thus, an image of a time point at which the electrode tip moves to the pressure developing space 244 by the operation of the welding robot 1 is obtained. At this time, the front end image and the side image of the electrode tip are obtained.

Next, when the second pulse signal is received, since the indentation 231a is formed on the pressure-sensitive paper 231 by the pressure of the electrode tip in the pressure developing space 244, the recorder 200 is moved through the driving unit 120. The motor 220 is operated to wind the pressure-sensitive paper 231 onto the second reel 233 by a predetermined length. Here, the predetermined length is such that the portion where the indentation 231a is formed in the pressure developing space 244 is moved to the photographing space 245. In this case, the predetermined length may be adjusted by the rotation angle of the second reel 233 or the second reel 233 of the pressure-sensitive paper 231 according to the length of the pressure-sensitive paper 231 previously wound on the second reel 233. It can be adjusted using a sensor that senses the length of the winding, and this adjustment method is known in the art related to the video tape, the description thereof will be omitted in the description of the embodiment of the present invention.

In this way, after the pressure-sensitive paper 231 is wound around the second reel 233 by a predetermined length, the vision sensor 300 is operated through the driving unit 120 to obtain an image. At this time, an image of the indentation 231a is obtained.

Next, the image processor 150 extracts an image of the indentation 231a, a front end image of each pair of electrode tips, and a side image from the captured image.

Next, the determination unit 160 determines the state of the electrode tip from the extracted image.

About the indentation 231a, after obtaining the diameter, area, shape, and concentration of the indentation 231a, it is determined as normal if the shape of the indentation 231a is circular and the diameter, area, and concentration are within a preset range.

In addition, when the shape of the indentation 231a is circular, but the diameter and area are outside the preset range, a command to polish the electrode tip or an alarm signal indicating that the polishing is required is transmitted to the welding robot 1 through the communication module 110. To polish the electrode tip with the tip dresser 30. At this time, it is good to inform that the polishing situation through the alarm unit 131.

In addition, when the shape of the indentation 231a is not circular, the alarm unit 131 may be alarmed to indicate that the electrode tip is not aligned or the electrode tip is in a bad state. Here, the misalignment of the electrode tip appears when the center axis of the pair of electrode tips does not coincide with each other and is misaligned, and the angle defect of the electrode tip appears when the central axis of at least one electrode tip of the pair of electrode tips is inclined. Thus, since the shape of the indentation 231a when the alignment of the electrode tip is poor and the shape of the indentation 231a when the angle of the electrode tip is poor, the alarm is distinguished according to the shape of the indentation 231a.

In addition, when the concentration of the indentation 231a is outside the preset range, the alarm to adjust the interval of the pair of electrode tips.

On the other hand, when the pressure-sensitive paper 231 is pressed by the welding robot 1, the indentation 231a is set by setting the operation of the welding robot 1 to press the middle point in the width direction of the pressure-sensitive paper 231 as the other point. It is possible to determine whether or not it is normal according to the degree of deviation from the intermediate point in the width direction of the pressure sensitive paper 231.

For each tip image of the electrode tip, the shape and color of the tip image are compared with the preset shape and color to determine the shape deformation and contamination of the electrode tip, and, for example, deviate from the preset shape or When a color other than a preset color is detected above a predetermined area, a signal to polish the electrode tip is transmitted to the welding robot 1.

For the side image of the electrode tip, the length of the electrode tip is detected from the side image and an alarm is issued to replace the electrode tip if less than a preset value. If the electrode tip is to be automatically replaced by the welding robot, the welding robot sends a signal to replace the electrode tip. Here, it is preferable to use that the electrode tip is formed along the circumference of the outer circumferential surface of the wear reference groove 23 showing the minimum length capable of functioning as the electrode tip.

As such, the result of determining the state of the electrode tip according to the image and the image acquired in conjunction with the welding robot 1 is stored in the data storage unit 140, and the statistical calculation unit 170 polishes the electrode tip from the history of the determination result. Statistical data of the cycle and the replacement cycle is generated and stored in the data preservation unit 140.

In this way, the image stored in the data storage unit 140, the state determination result history and statistical data of the electrode tip provides a data inquiry screen so that the manager of the production process can be inquired through the display unit 130.

FIG. 7 shows a recorder 200 showing that the lead-out part 241 and the recovery part 242 of the pressure-sensitive paper loading part 240 may be configured as

rollers

246a, 246b, 247a, and 247b in the embodiment of the present invention. Perspective perspective view of the.

Referring to FIG. 7, a plurality of

rollers

246a, 246b, 247a, and 247b are disposed in front of the surface of the cartridge 230 in which the outlet 234 and the recovery port 235 are formed.

At this time, the outlet 234 and the recovery port 235 is a plurality of rollers (246a, 246b, 247a, 247b) in the cartridge 230 as shown in FIG. Cut the whole face toward) to have an open shape.

In addition, the

rollers

246a, 246b, 247a, and 247b are the 1st roller 246a, the 2nd roller 246b, which are arrange | positioned at intervals on the line parallel to the line which connects the outlet opening 234 and the recovery opening 235, It consists of the 3rd roller 247a and the 4th roller 247b, and the 1st roller 246a and the 2nd roller 246b are arrange | positioned at the front of the outlet 234, and mutually spaced apart, The third roller 247a and the fourth roller 247b are disposed to be spaced apart from each other in front.

Accordingly, the pressure-sensitive paper 231 wound on the first reel 232 of the cartridge 230 is sequentially formed on the first roller 246a, the second roller 246b, the third roller 247a, and the fourth roller 247b. After running through the reel 235 is wound around the second reel 233 through the recovery port 235.

Here, the first roller 246a and the fourth roller 247b have a rotational axis parallel to the rotational axis of the first reel 232 and the second reel 233 of the cartridge 230, but the second roller 246b and the first roller 246a and the second roller 247b. The rotation axes of the three rollers 247a are parallel to each other, but the cartridges 230 are formed by making the rotation axes of the first roller 246a and the fourth roller 247b at the predetermined angle (90 ° in a specific embodiment of the present invention). Headed. Accordingly, when the pressure-sensitive paper 231 sequentially passes through the first roller 246a, the second roller 246b, the third roller 247a, and the fourth roller 247b, the pressure-sensitive paper 231 The width direction is gently rotated at the predetermined angle between the first roller 246a and the second roller 246b to face the cartridge between the second roller 246b and the third roller 247a, and then The roller is gently wound between the third roller 247a and the fourth roller 247b at the predetermined angle, and wound around the second reel 233 of the cartridge 230 without kinks.

Of course, as shown in the drawing, between the second roller 246b and the third roller 247a, the pressure developing space 244 through which the pressure-sensitive paper 231 passes between the two sheets of heat-insulating paper 243, and the pressure reduction An imaging space 245 is provided through which at least an indentation surface of both surfaces of the paper 231 is exposed.

By configuring the pressure-sensitive paper loading unit 240 with a roller as described above, the pressure-sensitive paper loading unit 240 is separated from the cartridge 230 and integrally mounted on the recorder 200, and only the cartridge 230 is manufactured as a separate type. It becomes easy. That is, the cartridge 230 is configured to wind the pressure-sensitive paper wound on the first reel to the second reel like a general video or audio tape cassette. When the cartridge 230 is mounted on the recorder 230, the recorder 230 includes the first roller 246a and the second roller 246 which are released from the first reel and pass between the first reel and the second reel. 246b), a driving means (not shown) which extends outward of the cartridge 230 after covering the third roller 247a and the fourth roller 247b is installed. Since such driving means (not shown) are known in the art related to the video tape recorder, only the characteristic description in the present invention which differs from the known driving means will be briefly described.

According to the present invention, the rotating shafts of the second roller 246b and the third roller 247a are parallel to the rotating shafts of the first and second reels when the cartridge 230 is mounted on the recorder 200, and the driving means ( (Not shown), it rotates at the predetermined angle so as to tilt toward the cartridge as shown in FIG.

The two parallel insulating sheets 243 are arranged to pass between the two insulating sheets 243 when the cartridge 230 is mounted on the recorder 230, and the second roller 246b and the third roller 247a are disposed. ) Is moved to the outside of the cartridge 230 to rotate together when the rotating shaft is rotated. Accordingly, as shown in FIG. 7, the pressure-sensitive paper loading unit 240 may be formed of a plurality of rollers.

Meanwhile, in the description of the embodiment of the present invention, the reel disk 211 inserted into the first reel 232 may be freely rotated. However, a tension adjusting device (not shown) for providing tension to the pressure-sensitive paper may include a first reel ( 232) is recommended. Such tension adjusting device (not shown) is well known in the art related to a video or audio recorder, and thus detailed description thereof will be omitted.

Although illustrated and described in the specific embodiments to illustrate the technical spirit of the present invention, the present invention is not limited to the same configuration and operation as the specific embodiment as described above, within the limits that various modifications do not depart from the scope of the invention It can be carried out in. Therefore, such modifications should also be regarded as belonging to the scope of the present invention, and the scope of the present invention should be determined by the claims below.

[Description of the code]

1: welding robot 2: robot arm

10: welding

gun

11a, 11b: shank

20a, 20b: electrode tip 21: tip surface 22: arc surface

23: wear standard groove

30: Tip Dresser

100: controller

110: communication module 120: drive unit 130: display unit

131: alarm unit 140: data storage unit 150: image processing unit

160: discrimination unit 170: statistics calculation unit

200: recorder

210: cartridge inlet 211,212: reel disk 220: motor

230: cartridge 231: pressure-sensitive paper 231a: indentation

232: first reel 233: second reel 234: outlet

235: recovery port 240: pressure-sensitive paper loading unit 241: withdrawal unit

242: recovery part 243: heat insulation paper 244: pressure developing space

245: shooting space 246a: first roller 246b: second roller

247a: third roller 247b: fourth roller

300: vision sensor

310: camera 320: reflector

Claims

The spot welding electrode tip polishing confirmation device which is fixed to the spot welding gun mounted on the welding robot and presses both sides of the spot to be welded with the welding material between them to the tip surface and inspects the pair of electrode tips for spot resistance welding. In

A recorder in which a pair of electrode tips pressurize both sides of the pressure-sensitive paper to form indentations while the pressure-sensitive paper wound on the first reel is unwound and wound on the second reel;

A vision sensor for photographing a portion where an indentation is formed before the pressure-sensitive paper is wound on the second reel;

A controller for extracting an indentation image from the image photographed by the vision sensor and determining a state of an electrode tip from the indentation image;

Spot welding electrode tip polishing check device, characterized in that comprising a.
The method of claim 1,

The recorder includes a pressure-sensitive paper loading unit for guiding the pressure-sensitive paper so that the pressure-sensitive paper released from the first reel passes through the pressure developing space exposing both sides of the pressure-sensitive paper and then wound on the second reel, and the pair of electrode tips in the pressure developing space. A spot welding electrode tip polishing confirmation device, characterized in that to pressurize both sides of the pressure-sensitive paper to form indentations.
The method of claim 2,

The recorder is configured such that the axial directions of the first reel and the second reel are parallel,

The pressure-sensitive paper loading unit is provided to protrude to the outside of the recorder, inclined the width direction of the pressure-sensitive paper released from the first reel at a predetermined angle to pass the pressure-developing space in a tilted state, and thereafter, the width of the pressure-sensitive paper The spot welding electrode tip polishing confirmation device, characterized in that to induce the pressure-sensitive paper so as to invert the direction in parallel with the axial direction of the second reel to wind the pressure-sensitive paper on the second reel.
The method of claim 3, wherein

Spot welding electrode tip polishing confirmation device, characterized in that the predetermined angle is 90 °.
The method of claim 4, wherein

The pressurizing developing space is provided with two sheets of flexible insulating paper covering both sides of the pressure-sensitive paper, pressurized by the pair of electrode tips while wrapped in two sheets of flexible insulating paper, and the pressure-sensitive paper passed between the two insulating papers is Spot welding electrode tip polishing confirmation device characterized in that the photographing space is provided to the pressure development space to be photographed by the vision sensor.
The method according to any one of claims 2 to 5,

A cartridge including the pressure-sensitive paper wound on the first reel, the second reel, and the first reel,

The recorder includes a mounting groove for inserting the cartridge, a reel disk installed in the mounting groove and inserted into the first reel and the second reel, and a motor for rotating the reel disk, so that the cartridge can be replaced. Spot welding electrode tip polishing confirmation device.
The method of claim 6,

Spot-pressure electrode tip polishing confirmation device, characterized in that the pressure-sensitive paper loading unit is integral with the cartridge.
The method of claim 6,

The controller is linked to the welding robot to form an indentation in the pressure-sensitive paper of the recorder at the time of rest during the welding process of the welding robot, and controls the recorder to wind the pressure-sensitive paper on the second reel with a predetermined length every time the indentation is formed, the indentation Spot welding electrode tip polishing confirmation device characterized in that the inspection of the wear state of the electrode tip using the diameter of the tip and the alignment inspection of the electric tip using the shape of the indentation and the inclination of the electrode tip.