Demonstration positioning method and demonstration positioning device for X-type spot welding pliers and spot welding robot

Abstract

The invention provides a teaching positioning method and device for an X-type spot welding clamp and a spot welding robot. The teaching positioning method for the X-type spot welding clamp comprises the following steps that a contact sensor is electrically connected to a fixed arm electrode and a welding workpiece of the X-type spot welding clamp; a position laser and an angle laser are installed on a movable arm of the X-type spot welding clamp, a preset included angle is formed between the optical axis of angle positioning laser emitted by the angle laser and the optical axis of the position positioning laser, and the angle positioning laser is focused on the welding workpiece to form a second light spot; in a welding state, when the position and the angle of a welding workpiece are normal, the first light spot coincides with the second light spot; in the welding state, when the position or angle of the welding workpiece is abnormal, the first light spot does not coincide with the second light spot. According to the invention, the position and angle of the welding workpiece can be inspected in the teaching process, a user can observe conveniently, and the teaching efficiency is improved.

Description

Technical Field

[0001] The invention relates to the technical field of welding, and more specifically to a teaching positioning method and a teaching positioning device for an X-type spot welding clamp. Background Art

[0002] With the rapid development of electronic computer technology, welding robots and mechanized and automated welding production lines are widely used in resistance welding production. The application of spot welding robots is mostly to carry spot welding tongs with robots to perform spot welding according to the program. In order to ensure the quality of welding, the spot welding robot must not only have sufficient load capacity, but also move quickly from point to point, move smoothly, and position accurately, so as to shorten the moving time and improve work efficiency.

[0003] The spot welding robot is suitable for welding large-sized, complex-shaped, inconveniently movable weldments and large thin-walled workpieces. The welding actuator is a spot welding clamp. One side of the spot welding clamp is fixed, while the other side performs the action of opening and clamping for welding. During spot welding, the upper and lower electrodes of the spot welding clamp should be pressed at the position to be welded at the same time, and the axis of the upper and lower electrodes should be along the normal direction of the surface of the part where the weld point is located to ensure the welding quality.

[0004] Spot welding tongs are divided into X-type spot welding tongs and C-type spot welding tongs. Generally, X-type spot welding tongs are required when the distance between the welding spot and the edge of the part exceeds 300mm. X-type spot welding tongs generally use a movable arm set under the part, and the welding spot position is taught or the teaching point is verified by observing the fixed arm.

[0005] When the robot arm is restricted by the part structure and the motion range of the robot arm, for example, when the space below the part is limited and the movable arm cannot be opened when it is below the part, the fixed arm can only be set below the part, and the weld point positioning and angle adjustment are performed on one side of the movable arm. Since the motion trajectory of the movable arm electrode of the X-type spot welding tongs is an arc line, when the spot welding tongs are opened and moved, the position of the movable arm electrode and the angle relationship with the part cannot be intuitively reflected, which brings great difficulties to the operation and leads to extremely low efficiency. Summary of the invention

[0006] 1. Technical issues to be resolved

[0007] The technical problem to be solved by the present invention is that when the existing X-type spot welding tongs use a movable arm electrode for teaching, the position of the movable arm electrode and the angle relationship with the part cannot be intuitively reflected, making the teaching efficiency extremely low.

[0008] (II) Technical solution

[0009] To achieve the above object, the technical solution adopted by the present invention is:

[0010] In a first aspect, the present invention provides a method for teaching and positioning an X-type spot welding clamp, comprising the following steps:

[0011] The contact sensor is electrically connected to the fixed arm electrode of the X-type spot welding clamp and the welding workpiece respectively;

[0012] A position laser is installed on the movable arm of the X-type spot welding tongs, the optical axis of the position laser emitted by the position laser coincides with the axis of the movable arm electrode, and when the X-type spot welding tongs is in a welding state, the optical axis of the position laser coincides with the axis of the stationary arm electrode, and the position laser is focused on the welding workpiece to form a first light spot;

[0013] An angle laser is installed on the movable arm of the X-shaped spot welding tongs, the optical axis of the angle positioning laser emitted by the angle laser is set at a preset angle with the optical axis of the position positioning laser, and the angle positioning laser is focused on the welding workpiece to form a second light spot;

[0014] In the welding state, when the position and angle of the welding workpiece are normal, the first light spot coincides with the second light spot; in the welding state, when the position or angle of the welding workpiece is abnormal, the first light spot does not coincide with the second light spot.

[0015] Preferably, the method further comprises the following steps:

[0016] In the welding state, when the contact sensor generates an electrical signal and the first light spot coincides with the second light spot, the corresponding welding point is saved as a teaching point;

[0017] In the welding state, when the contact sensor generates an electrical signal and the first light spot does not overlap with the second light spot, the welding clamp angle is adjusted to make the first light spot overlap with the second light spot.

[0018] Preferably, the preset angle is 30° to 60°.

[0019] Preferably, the color of the position positioning laser is different from the color of the angle positioning laser.

[0020] Preferably, the first light spot and the second light spot have the same shape and size.

[0021] Preferably, the first light spot and the second light spot are both circular in shape.

[0022] In the second aspect, the present invention also provides a teaching and positioning device for teaching the spot welding process of an X-type spot welding pliers, the X-type spot welding pliers comprising a fixed part, a stationary arm and a movable arm, the stationary arm being fixedly connected to the fixed part, the movable arm being rotatably connected to the fixed part, the movable arm being provided with a movable arm electrode, the stationary arm being provided with a stationary arm electrode, the teaching and positioning device comprising a contact sensor, a position laser and an angle laser; the contact sensor being electrically connected to the stationary arm electrode and the welding workpiece, the position laser being provided on the movable arm, and the optical axis of the position positioning laser emitted by the position laser coincides with the axis of the movable arm electrode, and when the X-type spot welding pliers is in a welding state, the optical axis of the position positioning laser coincides with the axis of the stationary arm electrode; the angle laser being provided on the movable arm, and the optical axis of the angle positioning laser emitted by the angle laser being arranged at a preset angle with the optical axis of the position positioning laser.

[0023] In a third aspect, the present invention further provides a spot welding robot, comprising a welding power source, an X-shaped spot welding tongs and the teaching positioning device as claimed in claim 7, wherein the welding power source is electrically connected to the X-shaped spot welding tongs.

[0024] (III) Beneficial effects

[0025] The above technical solution of the present invention has at least the following advantages:

[0026] In the present invention, the electrical signal generated on the contact sensor is used to determine whether the stationary arm electrode is in contact with the welding workpiece, thereby facilitating the observation of the contact condition of the stationary arm electrode located below the welding workpiece. A position positioning laser whose optical axis coincides with the axis of the movable arm electrode is used to irradiate the welding workpiece, so as to achieve the positioning of the position between the movable arm electrode and the welding workpiece. An angle positioning laser having a preset angle with the position positioning laser is used to irradiate the welding tooling, so as to achieve the positioning of the placement angle of the welding workpiece. The position and angle of the welding workpiece are judged by the coincidence of the position positioning laser and the angle positioning laser, so as to facilitate teaching programming. In the case where the space below the welding workpiece is limited, the method provided by the present invention is used for teaching, which not only simplifies the teaching process of complex welding workpieces with high requirements on the position and quality of the weld points, but also reduces the labor intensity of people and improves efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0028] Figure 1It is a structural schematic diagram of a teaching positioning device provided by an embodiment of the present invention.

[0029] Figure 2 It is a working principle diagram of the teaching positioning device provided by an embodiment of the present invention when the welding workpiece is in a normal position and angle state.

[0030] Figure 3 It is a schematic diagram of the light spot position of the teaching positioning device provided by an embodiment of the present invention when the welding workpiece is in a normal position and angle state.

[0031] Figure 4 It is a working principle diagram of the teaching positioning device provided by an embodiment of the present invention when the welding workpiece is in an abnormal state.

[0032] Figure 5 It is a schematic diagram of the light spot position of the teaching positioning device provided by an embodiment of the present invention when the welding workpiece is in an abnormal state.

[0033] The reference numerals in the figures are:

[0034] 10. X-type spot welding pliers; 11. Fixed part; 12. Fixed arm; 13. Moving arm; 121. Fixed arm electrode; 131. Moving arm electrode; 20. Welding workpiece; 1. Contact sensor; 2. Position positioning laser; 3. Angle positioning laser; A. First light spot; B. Second light spot. DETAILED DESCRIPTION

[0035] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0036] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly located on the other element or indirectly located on the other element. When an element is referred to as being "connected to" another element, it may be directly connected to the other element or indirectly connected to the other element.

[0037] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present invention, and do not indicate that a device or element must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the present invention.

[0038] In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating relative importance or indicating the number of technical features. In the description of the present invention, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined. The specific implementation of the present invention is described in more detail below in conjunction with specific embodiments:

[0039] like Figures 1 to 5 As shown, an embodiment of the present invention provides a teaching positioning device for teaching the spot welding process of an X-type spot welding pliers. The X-type spot welding pliers 10 includes a fixed part 11, a fixed arm 12 and a movable arm 13. The fixed arm 12 is fixedly connected to the fixed part 11, and the movable arm 13 is rotatably connected to the fixed part 11. The movable arm 13 is provided with a movable arm electrode 131, and the fixed arm 12 is provided with a fixed arm electrode 121. The teaching positioning device includes a contact sensor 1, a position laser and an angle laser; the contact sensor is electrically connected to the fixed arm electrode 121 and the welding workpiece 20, the position laser is arranged on the movable arm 13, and the optical axis of the position positioning laser 2 emitted by the position laser coincides with the axis of the movable arm electrode 131, and when the X-type spot welding pliers 10 is in a welding state, the optical axis of the position positioning laser 2 coincides with the axis of the fixed arm electrode 121; the angle laser is arranged on the movable arm 13, and the optical axis of the angle positioning laser 3 emitted by the angle laser is arranged at a preset angle with the optical axis of the position positioning laser 2.

[0040] An embodiment of the present invention provides a teaching positioning method for an X-type spot welding clamp, comprising the following steps:

[0041] The contact sensor 1 is electrically connected to the stationary arm electrode 12 of the X-shaped spot welding clamp 10 and the welding workpiece 20 respectively;

[0042] A position laser is installed on the movable arm 13 of the X-type spot welding tongs 10, and the optical axis of the position positioning laser emitted by the position laser coincides with the axis of the movable arm electrode 131, and when the X-type spot welding tongs 10 is in a welding state, the optical axis of the position positioning laser 2 coincides with the axis of the stationary arm electrode 121, and the position positioning laser 2 is focused on the welding workpiece 20 to form a first light spot A;

[0043] An angle laser is installed on the movable arm 13 of the X-shaped spot welding clamp 10. The optical axis of the angle positioning laser 3 emitted by the angle laser is set at a preset angle with the optical axis of the position positioning laser 2. The angle positioning laser 3 is focused on the welding workpiece 20 to form a second light spot B.

[0044] In the welding state, when the position and angle of the welding workpiece 20 are normal, the first light spot A coincides with the second light spot B; in the welding state, when the position or angle of the welding workpiece 20 is abnormal, the first light spot A coincides with the second light spot B.

[0045] Preferably, the method further comprises the following steps:

[0046] In the welding state, when the contact sensor 1 generates an electrical signal and the first light spot A coincides with the second light spot B, the corresponding welding point is saved as a teaching point;

[0047] In the welding state, when the contact sensor 1 generates an electrical signal and the first light spot A does not overlap with the second light spot B, the welding clamp angle is adjusted so that the first light spot A and the second light spot B overlap.

[0048] Specifically, the use principle of the teaching positioning device provided in this embodiment is as follows: the movable arm 13 is opened to a suitable opening position, the size of which is based on not interfering with the welding workpiece 20 when moving.

[0049] After adjusting the teaching positioning device, in normal use Figure 2 and Figure 3 As shown, during teaching, the weld point position is first calibrated on the upper surface of the welding workpiece 20. When the fixed arm electrode 121 contacts the welding workpiece 20, the center of the first light spot A should coincide with the calibrated weld point position. At the same time, the center of the second light spot B also coincides with the calibrated weld point position. At this time, it means that the position and angle of the X-type spot welding clamp 10 are appropriate and can be saved as a teaching point.

[0050] When the axial direction of the X-type spot welding clamp 10 does not coincide with the normal direction of the weld spot position calibrated on the welding workpiece 20, such as Figure 4 and Figure 5 As shown, when the fixed arm electrode 121 contacts the welding workpiece 20, the center of the first light spot A should coincide with the calibrated welding spot position. At this time, due to the inappropriate angle, the upper surface point of the welding workpiece 20 is higher than the theoretical position, resulting in the center of the second light spot B not coinciding with the calibrated welding spot position. The deflection angle of the center of the second light spot B can reflect the deflection direction of the X-type spot welding pliers 10. At this time, the adjustment can be completed by adjusting the angle of the X-type spot welding pliers 10 until the center of the first light spot A and the center of the second light spot B coincide with the calibrated welding spot position. The entire adjustment process does not require observation of the contact between the bottom of the welding workpiece 20 and the fixed arm electrode 121.

[0051] Preferably, the preset angle is 30° to 60°. Specifically, within this range, the larger the preset angle is, the more sensitive the detection is.

[0052] Preferably, the color of the position positioning laser 2 is different from the color of the angle positioning laser 3. By setting the color of the position positioning laser 2 and the color of the angle positioning laser 3 to be different, it is convenient to observe and distinguish them during the teaching process.

[0053] Preferably, the first light spot A and the second light spot B are the same in shape and size.

[0054] Preferably, the first light spot A and the second light spot B are both circular in shape.

[0055] The following is a specific embodiment provided by this application:

[0056] The welding workpiece 20 is a large hyperbolic wall panel, and the position accuracy of the welding points is required to be high. The overall size of the welding workpiece 20 is about 1.5mx3.0m, and its curved surface is constantly changing, and the number of welding points is large. During the spot welding teaching, the movable arm 13 cannot be positioned downward against the fixed arm 12, and the welding clamp angle of each welding point needs to be adjusted in real time. Due to the large size of the welding workpiece 20 and the small space below, the situation of the fixed arm electrode 121 and the welding workpiece 20 below the welding workpiece 20 cannot be observed.

[0057] When teaching by using the teaching positioning device of the present invention, the position of the welding spot is first marked at the welding location of the welding workpiece 20 to be welded, and then the position and angle of the welding clamp are adjusted by using the teaching positioning method of the X-type spot welding clamp in the above embodiment, and the teaching of hundreds of welding spots on the entire welding workpiece 20 is completed. The welding effect realizes spatter-free welding.

[0058] The present invention further provides a spot welding robot, comprising a welding power source, an X-shaped spot welding clamp 10 and a teaching positioning device as claimed in claim 7, wherein the welding power source is electrically connected to the X-shaped spot welding clamp 10.

[0059] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A teaching positioning method for X-type spot welding pliers, characterized in that: The following steps are involved: The contact sensor is electrically connected to the fixed arm electrode of the X-type spot welding clamp and the welding workpiece respectively; A position laser is installed on the movable arm of the X-type spot welding tongs, the optical axis of the position laser emitted by the position laser coincides with the axis of the movable arm electrode, and when the X-type spot welding tongs is in a welding state, the optical axis of the position laser coincides with the axis of the stationary arm electrode, and the position laser is focused on the welding workpiece to form a first light spot; An angle laser is installed on the movable arm of the X-shaped spot welding tongs, the optical axis of the angle positioning laser emitted by the angle laser is set at a preset angle with the optical axis of the position positioning laser, and the angle positioning laser is focused on the welding workpiece to form a second light spot; In the welding state, when the position and angle of the welding workpiece are normal, the first light spot coincides with the second light spot; in the welding state, when the position or angle of the welding workpiece is abnormal, the first light spot does not coincide with the second light spot.

2. The X-type spot welding clamp teaching positioning method according to claim 1, characterized in that: The following steps are also included: In the welding state, when the contact sensor generates an electrical signal and the first light spot coincides with the second light spot, the corresponding welding point is saved as a teaching point; In the welding state, when the contact sensor generates an electrical signal and the first light spot does not overlap with the second light spot, the welding clamp angle is adjusted to make the first light spot overlap with the second light spot.

3. The X-type spot welding clamp teaching positioning method according to claim 1, characterized in that: The preset angle is 30° to 60°.

4. The X-type spot welding clamp teaching positioning method according to claim 1, characterized in that: The color of the position positioning laser is different from the color of the angle positioning laser.

5. The X-type spot welding clamp teaching positioning method according to claim 1, characterized in that: The first light spot and the second light spot have the same shape and size.

6. The X-type spot welding clamp teaching positioning method according to claim 1, characterized in that: The first light spot and the second light spot are both circular in shape.

7. A teaching positioning device, used for teaching the spot welding process of an X-type spot welding tongs, the X-type spot welding tongs comprising a fixed part, a fixed arm and a movable arm, the fixed arm is fixedly connected to the fixed part, the movable arm is rotatably connected to the fixed part, the movable arm is provided with a movable arm electrode, and the fixed arm is provided with a fixed arm electrode, characterized in that: The teaching positioning device includes: A contact sensor electrically connected to the stationary arm electrode and the welding workpiece; A position laser is arranged on the movable arm, and the optical axis of the position positioning laser emitted by the position laser coincides with the axis of the movable arm electrode, and when the X-type spot welding clamp is in a welding state, the optical axis of the position positioning laser coincides with the axis of the stationary arm electrode; The angle laser is arranged on the movable arm, and the optical axis of the angle positioning laser emitted by the angle laser is arranged at a preset angle with the optical axis of the position positioning laser.

8. A spot welding robot, characterized in that: It comprises a welding power source, an X-shaped spot welding tongs and the teaching positioning device as claimed in claim 7, wherein the welding power source is electrically connected to the X-shaped spot welding tongs.

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