KR20190014823A - Brazing Joint Apparatus for Metal Pipes and Method thereof - Google Patents

Abstract

The present invention relates to a brazing bonding apparatus for a metal pipe, which comprises: a multi-joint robot arm; a bonding housing coupled to a terminal end of the multi-joint robot arm, clamping the metal pipe, and including a resistance heating electrode for heating the clamped metal pipe at a brazing temperature; a temperature sensor installed in a bonding head and detecting the temperature of a bonding portion of the metal pipe; a vision sensor installed in the bonding head and detecting the position of the bonding portion of the metal pipe; a welding additive support means installed in the bonding head and supplying a welding additive to the position of the bonding portion of the metal pipe; and a control means. According to the present invention, the control means executes a metal pipe brazing bonding control program. Accordingly, a copper pipe brazing bonding head is coupled to the robot arm, such that a brazing bonding operation for a copper pipe is automated, thereby capable of improving productivity.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a brazing joint apparatus for metal pipes,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a metal pipe brazing and bonding apparatus, and more particularly, to a brazing apparatus for automatically joining a refrigerant pipe of a cooling system such as an air conditioner or a refrigerator, To a pipe brazing joint device.

In products such as refrigerators and air conditioners, copper pipes are mainly used as refrigerant circulation channels for cooling systems. The used copper pipe is used by connecting the copper pipes to the desired length by the brazing method in the course of forming the refrigerant circulation passage.

Therefore, the applicant of the present invention has patented a copper pipe brazing device using a carbon heating element (Patent Registration No. 10-0829546), which is free of fire hazard and easy to use.

Since the registered patent is manufactured as a clamp type which is easy for the workers to carry on the field, it is convenient for the user to work on the field, and the unskilled can easily use it.

However, the production lines of refrigerators and air conditioners required automation to improve productivity. However, only the refrigerant pipe joint was not automated, and the worker manually handled the production line.

Patent No. 10-0001838 Patent No. 10-1609160 Patent No. 10-1412650 Patent No. 10-1265552 Patent No. 10-0969007 Patent No. 10-0704809

SUMMARY OF THE INVENTION It is an object of the present invention to provide an apparatus and a method for joining a metal pipe brazing capable of improving productivity by automatically joining a refrigerant pipe of a cooling system such as a refrigerator and an air conditioner.

According to an aspect of the present invention, there is provided a metal pipe brazing joining apparatus comprising: a multi-axis robot arm; A joining head coupled to an end of the multi-axis robot arm; A clamping means formed on one end of the joint head and clamping the metal pipe and having a resistance heating electrode for heating the clamped metal pipe to the brazing temperature; Power supply means built in the joint head and for supplying electric energy to the electrode of the clamping means; A temperature sensor installed at the joint head for sensing the temperature of the junction of the metal pipe; A vision sensor installed on the joint head for detecting a position of a joint portion of the metal pipe; A filler material supply means installed on the joint head for supplying the filler material to a position of the joint portion of the metal pipe; And control means. Wherein the control means performs a metal pipe brazing joint control program.

The metal pipe brazing joint control program controls the multi-axis robot arm to move the joint head to the vicinity of the connection part of the detected metal pipe, detect the connection part of the metal pipe through the vision sensor, control the clamping part, And the metal pipe clamped through the electrode is energized to heat the connecting portion to detect the temperature of the connecting portion through the temperature sensor and when the detected temperature reaches the brazing temperature, Melting the molten metal by bringing the molten metal into contact with the connecting portion, detecting the bonding state of the connecting portion through the vision sensor, and cutting off the current supply to the electrode when the bonding is completed. Therefore, productivity improvement can be expected by automating the brazing joint work of the copper tube by connecting the copper tube brazing joint head to the robot arm.

In the present invention, the electrode provided on the clamp means is preferably formed of a tungsten electrode.

In the present invention, the filler supplying means is provided on the left and right sides of the vision sensor, respectively, so that the brazing operation speed can be improved by simultaneously supplying the silver wire to both sides of the joint portion of the metal pipe.

The apparatus of the present invention further includes a flux injecting means installed in the junction housing and injecting flux to the connecting portion of the metal pipe. Here, the control means may further include an operation of controlling the flux injecting means and injecting the flux to the connection portion of the metal pipe before the electric current is supplied to the electrode.

A method of joining a metal pipe brazing according to the present invention is a method for joining a metal pipe to a metal pipe, Detecting a connection portion of the metal pipe through the vision sensor; Clamping the connection portion of the metal pipe by controlling the clamp means when the connection portion is detected; Heating the connection portion of the metal pipe by applying a current to the clamped metal pipe through the electrode provided on the clamping means to generate resistance; Detecting a temperature of the connection portion of the metal pipe through the temperature sensor; When the detected temperature reaches the brazing temperature, controlling the filler supplying means to contact and melt the filler on the joint of the metal pipe; Detecting a junction state of a connection portion of the metal pipe through the vision sensor; And blocking the current supply to the electrode when the bonding is completed.

As described above, in the present invention, productivity improvement can be expected by automating the brazing operation of the refrigerant pipe of the cooling system by using the robot arm.

However, the effects of the present invention are not limited to the above-mentioned effects, and other effects not mentioned above can be clearly understood by those skilled in the art without departing from the spirit and scope of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a view for explaining a preferred embodiment of a joining apparatus for a metal arm type of a robot arm according to the present invention. Fig.
Fig. 2 is a block diagram of a preferred embodiment of a metal pipe brazing joint device in the form of a robot arm of Fig. 1; Fig.
Figure 3 is a front view of the brazing joint head of Figure 1,
Fig. 4 is a right side view of the brazing joint head of Fig. 1; Fig.
5 is an enlarged view of a portion A in Fig.
6 is a sectional view taken along the line AA in Fig. 5;
7 is a flowchart for explaining the operation of a robot arm type metal pipe brazing jointing apparatus according to the present invention.
8 is a screen state view showing a pipe clamp position picked up by the vision sensor;
Fig. 9 is a view of the screen before the brazing joint operation picked up by the vision sensor. Fig.
Fig. 10 is a view of a screen after brazing operation picked up by the vision sensor. Fig.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. This embodiment is described in sufficient detail to enable those skilled in the art to practice the invention.

Fig. 1 shows a preferred embodiment of a metal pipe brazing joint device in the form of a robot arm according to the present invention, and Fig. 2 shows a block diagram of a preferred embodiment of a metal pipe brazing joint device in the form of a robot arm of Fig.

Referring to FIG. 1, the metal pipe brazing joint apparatus 10 of the present invention includes a multi-axis robot 100 having a brazing joint head 120 at the end of a multi-axis robot arm 110 and a movable control panel 200. The control panel 200 includes display means 210 such as a monitor, input means 220 such as a keyboard and a mouse, and control means 230 such as a computer.

Referring to FIG. 2, the brazing joint head 120 includes clamping means 120a, filler supplying means 120b and 120c, a vision sensor 129d, a temperature sensor 120e and a flux injecting means 120g.

FIG. 3 is a front view of the brazing joint head of FIG. 1, FIG. 4 is a right side view of the brazing joint head of FIG. 1, FIG. 5 is an enlarged view of A of FIG. 3, and FIG. 6 is a cross-sectional view taken along line A-A of FIG.

Referring to the drawing, the brazing joint head 120 has a fastening flange 124 for fastening the robot arm 110 to one end of the housing 122, and a clamping means 120a is coupled to the other end. The brazing joint head 120 is threaded onto the end of the robot arm 110 via the fastening flange 124. [ The clamp means 120a includes the " a " -shaped fixing member C1 and the movable member C2. One end of the vertical portion C1a of the fixing member C1 is fixed to the other end of the housing 122 and an air cylinder C3 is installed in the housing 122. [ The rod C4 of the air cylinder C3 is projected from the air cylinder C3 toward the horizontal portion C1b of the fixing member C1. A guide groove C1c is formed in the vertical portion C1a of the fixing member C1. A guide rail C2a of the movable member C2 is inserted and guided in the guide groove C1c. The movable member C2 has a front surface facing the inner surface of the horizontal portion C1b of the fixing member C1. The rear surface of the movable member C2 is coupled to the end of the rod C4 of the air cylinder C3. Therefore, the movable member C2 is moved back and forth along the guide groove C1c by the reciprocating motion of the rod C4 of the air cylinder C3. Here, the driving means of the movable member C2 has been described as an air cylinder and a rod structure, but not limited thereto, a server motor, a linear motor, or the like can be used.

The first electrode E1 is screwed onto the inner surface of the horizontal portion C1b of the fixing member C1 so as to protrude toward the movable member C2. The second electrode E2 is screwed on the front surface of the movable member C2 so as to protrude toward the first electrode E1 of the fixing member C1. Grooves E1a and E2a are formed on the opposite surfaces of the electrodes E1 and E2, respectively. The grooves E1a and E2a have a radius of curvature circumscribed on the outer surface of the large diameter copper pipe P1 to be superposed on each other. The electrodes E1 and E2 are made of tungsten.

Filler supply means 120b and 120c, a vision sensor 120d, a temperature sensor 120e and a flux spraying means 120g are installed on one side surface of the vertical portion C1a of the fixing member C1. 5, in the embodiment of the present invention, the vision sensor 120d is disposed on the center line of the clamping space facing the electrodes E1 and E2, and the scraped material supply means 120b and 120c are disposed on the left and right sides, respectively . The temperature sensor 120e is disposed at a position different from the height of the vision sensor as shown in Fig. The flux injecting means 120g is disposed between the vision sensor 120d and the filler supplying means 120c.

The consumable material supply means 120b and 120c are each constituted by a normal wire reel passing wire supply drive box. The consumable material supply means 120b and 120c are arranged such that the ends of the supplied silver wires AW1 and AW2 are positioned on the ends of the large diameter pipe P1 in the clearance between the overlapping portions of the large diameter pipe P1 and the small diameter pipe P2 The azimuth can be adjusted. As shown in Fig. 5, the ends of the silver wire AW1 and AW2 are brought into contact with one end of the large-diameter pipe P1 and supplied to be melted by the heat transmitted from the heated large-diameter pipe P1. In the present invention, the fugitive material supply means 120b and 120c are melted by simultaneously contacting the silver wire AW1 and AW2 from both sides of the pipe, so that the gap between the pipes is quickly filled, and thus the work speed can be increased. The molten fugant solution is wetted by the capillary phenomenon caused by the surface tension, and when it is cooled, it coagulates and the pipe gap can be sealed tightly.

The vision sensor 120d is constituted by a small camera composed of a solid-state image sensor and has a resolution of HD class or higher. The vision sensor 120d preferably includes a zooming function. During the clamping operation, the pipe connection portion to be clamped is detected to be infinite. In order to detect the bonding state, the bonding region of the pipe is zoomed and the bonding state image of the silver halide is photographed.

As shown in FIG. 6, the temperature sensor 120e is formed of a non-contact type infrared temperature sensor for measuring the temperature of the outer surface of the large diameter pipe P1.

 The flux injecting means 120g injects the flux into the pipe connection gap to apply the flux to the bonding region. When the flux is mixed with the silver wire, the flux injecting means can be removed.

The operation and effect of the present invention constructed as described above are as follows.

FIG. 7 is a flow chart for explaining the operation of a robot arm type metal pipe brazing jointing apparatus according to the present invention, FIG. 8 is a screen state view showing positions of pipe clamps picked up by a vision sensor, FIG. FIG. 10 is a screen state diagram after picked-up brazing operation by the vision sensor. FIG.

Referring to FIG. 7, the control means 230 executes a metal pipe brazing joint control program when a joint work command is received. First, the control unit 230 controls the multiaxial robot arm 110 to scan the pipe to the vision sensor 120d, and detects the connection part of the pipe (S10). Since the pipe connection part has a step due to the diameter difference of the pipe (P1, P2), it can be easily detected through the image analysis algorithm (bounding line extraction algorithm). The connection portion detected by the vision sensor 120d is determined as a portion where a step exists as shown in FIG.

Subsequently, the control means 230 micro-manipulates the multi-axis robot arm 110 to move the bonding head 120 to the clamping position of the connection site (S12). As shown in Fig. 8, a clamp rectacle is displayed on the screen of the display means 210 to process access control of the connection site of the bonding head 120. Fig.

Next, when approaching the connecting portion of the control means 230, the pipe is positioned between the fixed member C1 and the movable member C2 of the clamp means 120a, and then the movable member C2 of the clamp means 120a is pushed And the pipe is clamped between the two electrodes E1 and E2 (S14). The completion of the clamping is determined as the moment when the electrode image pattern coincides with the predetermined retardation.

When the clamping operation of the connecting portion is completed through the robot arm 110 and the clamping means 120a, the control means 230 controls the flux injecting means 120g to spray the flux to the connecting portion to apply the flux S16).

Subsequently, current is passed through the two electrodes E1 and E2 of the clamping means 120a (S18). When a current is supplied, resistance heat is generated by the resistance of the contact surface between the pipe and the electrodes E1 and E2, and the surface temperature of the pipe rises due to this heat generation. The control means 230 detects that the temperature of the pipe is heated to a brazing temperature of 400 DEG C or higher through the temperature sensor 120e (S20).

When the heating means 230 is heated to a sufficient brazing temperature, the control means 230 supplies the heating wires AW1 and AW2 to the heated pipe through the consumable material supplying means 120b and 120c. Fig. 9 shows an image of the supplied silver wire AW1, AW2 in contact with the heated pipe. Therefore, the control means 230 analyzes the screen image of FIG. 9 and controls the consumable material supplying means 120b and 120c.

The supplied silver wire (AW1, AW2) is melted by conduction heat when it comes into contact with the pipe.

The melted filler rubs through the pipe crevices and becomes wet by the surface tension and the capillary phenomenon. Therefore, the joints of the two copper pipes P1 and P2 are tightly and firmly sealed (S22).

The control means 230 detects the state of the wet silvered profile through the image analysis of FIG. 10 (S24). When the pipe filling of the filler metal is completed by this detection, the control means interrupts the current applied to the electrodes E1 and E2, stops supplying the filler through the filler supplying means 120b and 120c, and ends the brazing operation (S26).

When the bonding operation is completed, the control means 230 analyzes the image profile of the bonding region and analyzes whether the bonding state is bad or not.

 It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the present invention as defined by the following claims It can be understood that For example, the clamping means may be configured in a clamping configuration.

100: Multi-axis robot
110: Robot arm
120: bonding head
120a: Clamp means
120b, and 120c:
120d: Vision sensor
120e: Temperature sensor
200: control panel
210: display means
220: input means
230: control means

Claims (6)

A metal pipe brazing joint device for lap jointing metal pipes,
Multi - axis robot arm; A joining head coupled to an end of the multi-axis robot arm; A clamping means formed on one end of the joint head and clamping the metal pipe and having a resistance heating electrode for heating the clamped metal pipe to a brazing temperature; A temperature sensor installed at the joint head for sensing a temperature of a joint portion of the metal pipe; A vision sensor installed on the joint head and detecting a position of a joint portion of the metal pipe; And a control means for supplying a filler material to a position of a joining portion of the metal pipe,
The control means performs a metal pipe brazing joint control program,
The metal pipe brazing joint control program
Axis robot arm to move the joining head to a vicinity of a connection part of the detected metal pipe, detect a connection part of the metal pipe through the vision sensor, control the clamping part to clamp the connection part of the metal pipe, A connection portion is heated by applying a current to the metal pipe clamped through the electrode, a temperature of the connection portion is detected through the temperature sensor, and when the detected temperature reaches the brazing temperature, the control means controls the filler supply means And melting and melting the joining material by contacting the joining material with the joining material, detecting the joining state of the joining material through the vision sensor, and cutting off the current supply to the electrode when joining is completed. The metal pipe brazing and bonding apparatus according to claim 1, wherein the electrode provided on the clamping means is a tungsten electrode. [2] The method according to claim 1,
And a silver wire brazing welding device installed on both sides of the vision sensor to supply silver wire to both sides of the joining portion of the metal pipe at the same time. The apparatus of claim 1,
Further comprising a flux injecting means provided in the joint head for injecting a flux to a connecting portion of the metal pipe,
Wherein the control means further comprises an operation of controlling the flux injecting means to inject flux to the connecting portion of the metal pipe before applying current to the electrode. A metal pipe brazing method for lap jointing metal pipes,

A multidirectional robot arm to control the movement of the joint head to the vicinity of the connection of the detected metal pipe;
Detecting a connection portion of the metal pipe through the vision sensor;
Clamping the connection portion of the metal pipe by controlling the clamp means when the connection portion is detected;
Heating a connection portion of the metal pipe by applying a current to the metal pipe clamped through the electrode provided on the clamping means and generating resistance;
Detecting a temperature of the connection portion of the metal pipe through the temperature sensor;
When the detected temperature reaches the brazing temperature, controlling the filler supplying means to contact and melt the filler on the joint of the metal pipe;
Detecting a junction state of a connection portion of the metal pipe through the vision sensor; And
And disconnecting the current supply to the electrode when the bonding is completed. 6. The method of claim 5, further comprising the step of spraying the flux at a connection site of the metal pipe by controlling the flux injection means before energizing the electrode.

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