JPH07303967A - Device for switching welding condition of stud welding equipment - Google Patents

Abstract

PURPOSE:To prevent generation of the defective weld due to incorrect switching of the welding condition when the stud welding is performed to a work of different hole position according to the plate thickness. CONSTITUTION:The presence/absence of a hole at the prescribed part of a work 8 loaded on a jig rotating base 7 is detected by a hole detecting unit 10, a sensing board 26 is vertically moved through a cylinder rod 25 of an air cylinder 21 based on the detected output, a proximity switch 6 is turned on or turned off by the approaching or separating operation of this sensing board 26, and the ON/OFF signal of this proximity switch 6 is inputted to a controller as the switching signal of the welding condition.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a welding condition switching device for a stud welding device that automatically switches welding conditions according to the plate thickness of a work.

[0002]

2. Description of the Related Art Stud welding is performed by welding a stud to a workpiece by first generating a pilot arc and then generating a main arc to press the stud against the welding portion while the stud is close to the welding portion of the workpiece. Therefore, various proposals have been made regarding such a stud welding technique (for example, JP-A-5-376, JP-A-63-203278 and JP-A-63-235).
078 gazette etc.).

When stud welding is performed on an assembly part of an automobile or the like, the plate thickness may differ depending on the type of vehicle. Since welding conditions such as the current value during the pilot arc and main arc during stud welding differ depending on the plate thickness,
It is necessary to switch the welding condition for each different work thickness. By the way, there are
There are some parts that have the same shape but differ in the location of the holes depending on the plate thickness.

Therefore, when stud welding is performed on such a work, conventionally, a part of the work is specified, and an operator visually confirms whether or not there is a hole at the specified part, and Welding conditions are switched between work with and without work.

[0005]

However, in such a method in which the operator visually confirms and switches the welding conditions as described above, the welding conditions may be erroneously set due to the operator's erroneous recognition of the presence or absence of a hole or misunderstanding. , Welding failure occurs due to non-conformity of welding conditions. It is also possible to measure the plate thickness of the work directly with a sensor and switch the welding condition based on the measured value, but in order to measure the plate thickness accurately, it is necessary to prepare the measurement condition. However, the equipment becomes complicated and expensive. In addition, there is a problem that the thickness cannot be measured in some parts depending on the shape of the work.

In Japanese Utility Model Laid-Open No. 2-97974, a welding condition is detected based on the displacement amount by detecting a difference in plate thickness based on a displacement amount of an electrode tip when a work is pressed and clamped during welding. Although a welding condition switching device for a spot welding device having a configuration for switching between the two is disclosed, the welding method is different between spot welding and stud welding, and this technique cannot be directly applied to the stud welding that is the subject of the present invention. .

The present invention has been made in view of the above circumstances, and when performing stud welding on a work in which the drilling position differs depending on the plate thickness, it is not necessary to visually check the holes, and proper welding conditions are ensured. An object of the present invention is to provide a welding condition switching device for a stud welding device that can be set and prevent the occurrence of welding defects.

[0008]

Therefore, in the present invention,
In the welding condition switching device of the stud welding device configured to switch the welding conditions according to the plate thickness of the work when stud welding is performed by positioning the work with different hole drilling positions depending on the plate thickness in the rotary welding jig, A structure comprising plate thickness detecting means for detecting the plate thickness by detecting the presence or absence of a hole in the same predetermined portion of the work, and control means for switching control of welding conditions based on the detection output of the plate thickness detecting means; did.

The plate thickness detecting means of the apparatus of the present invention is slidably supported in the vertical direction on the work mounting rotary base of the rotary welding jig, and the work having a hole at the predetermined portion is mounted thereon. When the workpiece having no hole in the predetermined portion is placed by the elastic biasing force of the elastic member, the weight of the workpiece resists the elastic biasing force of the elastic member. A hole detection rod that descends and is held at a lower limit position, and a cylinder rod that has two fluid pressure chambers that are vertically partitioned by a piston and that is capable of expanding and contracting in conjunction with the piston face downward with the lower surface of the rotating base. A fluid pressure cylinder fixed to the fluid pressure cylinder, a fluid pressure supply source connected to two fluid pressure chambers of the fluid pressure cylinder via a fluid pressure supply passage so that the fluid pressure can be supplied, and a tip end of the cylinder rod of the fluid pressure cylinder. Fixed A movable body that moves in the vertical direction as the cylinder rod expands and contracts, and a jig pedestal side that is fixed to a fixed part and rotatably supports the rotary shaft of the rotary base so as to face the movable body. A proximity switch that turns on and off according to the approaching / separating motion of the body, and a fluid pressure chamber that is mechanically connected to the lower end of the hole detection rod and supplies fluid pressure according to the lower end position of the hole detection rod are selectively A fluid pressure supply passage switching means for switching may be provided, and an ON / OFF signal of the proximity switch may be output to the control means.

[0010]

In the structure of claim 1, the work is positioned and set on the rotary welding jig. The plate thickness detecting means detects whether or not there is a hole in a predetermined part of the set work set in advance. The control means switches to welding conditions suitable for the plate thickness of the work set based on the detection output from the plate thickness detection means depending on the presence or absence of the hole.

As a result, the reliability is higher than when the operator visually confirms the presence or absence of the hole, and the welding conditions can be accurately switched and set. Further, in the structure of claim 2, when there is a hole in the work, the hole detection rod is held at the upper limit position by penetrating the hole by the elastic biasing force of the elastic member. With the placement, the hole detection rod abuts against the work, and the weight of the work lowers against the elastic biasing force of the elastic member and is held at the lower limit position. The mechanical fluid pressure supply passage switching means operates according to the difference in the hole detection rod position depending on the presence or absence of such a hole, so that the fluid pressure from the fluid pressure supply source is one of the two fluid pressure chambers of the fluid pressure cylinder. The cylinder rod of the fluid pressure cylinder expands and contracts, and the moving body approaches or separates from the proximity switch. The proximity switch is turned on or off as the moving body approaches or separates, and outputs the on or off signal to the control means as a detection output of the plate thickness detection means.

Then, the presence or absence of a hole (that is, the plate thickness) is detected in the rotating portion on which the work is placed, and the detection output is controlled by the proximity switch provided on the fixed portion side that rotatably supports the rotating portion. Since the output is provided to the means, the electrical wiring that connects the proximity switch and the control means is not entangled by the rotating operation of the rotating portion. Further, since electrical wiring is not required between the rotating portion and the fixed portion, it is not necessary to use a brush having a problem with durability, and the durability of the device is improved.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. 1 and 2 show an embodiment of a welding condition switching device of a stud welding device according to the present invention. 1 and 2
In, for example, the jig base 2 is fixed to the floor surface 1,
A rotary shaft 4 is rotatably supported by the jig pedestal 2 via a fixed shaft 3, and a proximity switch 6 is mounted on the upper surface of the jig pedestal 2 via a bracket 5. .

At the upper end of the rotary shaft 4, a circular jig rotating base 7 for placing a work as shown in FIG. 2 is fixed. A plurality of bearings 9 for supporting the work 8 above the jig rotating base 7 are provided around the upper surface and the central portion of the jig rotating base 7. The positions of these bearings 9 can be changed according to the shape of the work 8. A hole detection unit 10 for detecting the presence or absence of holes in the work 8 is provided at the center of the jig rotating base 7.

As shown in FIG. 3, the hole detecting unit 10 includes a base 11 fixed to the upper surface of the jig rotating base 7, and the base 11
Bracket 12 fixed upright on the
Through the vertical direction, and the collar at the middle.
A hole detecting rod 13 having 13A, and an elastic member that is interposed between the flange portion 13A of the hole detecting rod 13 and the bracket 12 and that always elastically urges the hole detecting rod 13 upward through the flange portion 13A. The coil spring 14, a cylindrical guide member 15 through which the hole detection rod 13 penetrates and guides the sliding movement of the hole detection rod 13, and fixed to the base 11 and connected to the lower end of the hole detection rod 13 via a lever 16. And a mechanical valve 17 that operates. One end of the lever 16 is rotatably connected to the lower end of the hole detecting rod 13, and the other end is a mechanical valve interposed in an air supply passage 32 described later for supplying air as fluid pressure as shown in FIG.
It is fixed to the shaft portion 17a of 17.

When the work 8 has the hole 8a as shown in FIG. 3A, the hole detecting rod 13 is held at the upper limit position by penetrating the hole 8a by the elastic biasing force of the coil spring 14.
When there is no hole in the work 8 as shown in (B), the hole detection rod 13
Is lowered by the weight of the work 8 against the elastic biasing force of the coil spring 14 and held at the lower limit position. Then, the lever 16 rotates according to the holding position of the hole detection rod 13,
The mechanical valve 17 is operated as described later.

As shown in FIGS. 1 and 2, two air cylinders 21 serving as fluid pressure cylinders are fixed to the lower surface of the jig rotating base 7. As shown in FIG. 4, the inside of each air cylinder 21 is partitioned by a piston 22 into two air chambers 23 and 24 as fluid pressure chambers.
The cylinder rod 25 is fixed to. The cylinder rod 25 expands and contracts as the piston 22 moves up and down. The air cylinder 21 is fixed so that the cylinder rod 25 faces downward, and a sensing plate 26 as a ring-shaped moving body surrounding the rotating shaft 4 is fixed to the tip end of the cylinder rod 25. 26 moves up and down integrally with the cylinder rod 25 and separates from or approaches the proximity switch 6 arranged facing each other.

Next, the air supply path of the air cylinder 21 is shown in FIG. 4 and will be described. Air chambers 23 and 24 of air cylinder 21
The air pressure source 31 as a fluid pressure supply source is connected by the air supply passage 32 described above. This air supply passage
The mechanical valve 17 and a switching valve 33 as a fluid pressure supply passage switching means are interposed in the valve 32, and the switching valve 33 is provided with a signal pressure from an air pressure source 31 supplied through the mechanical valve 17. The supply of air to the air chambers 23 and 24 of the air cylinder 21 is selectively switched by the switching operation. When the sensing plate 26 approaches or separates from the proximity switch 6 by the vertical movement of the cylinder rod 25 accompanying the switching of the supply of the air pressure, an ON or OFF signal is generated from the proximity switch 6, and this ON or OFF signal is generated. Is input to a controller 34 as control means, and the controller 34 determines the plate thickness of the work 8 based on the input signal and automatically switches and sets welding conditions. Here, the air pressure source 31 is installed on the floor surface 1 side, and the air supply passage 32 to the air cylinders 21, 21 on the jig rotating base 7 side is freely rotatable with respect to each other at the boundary portion between the fixed portion and the rotating portion. It is configured to be connected, and the connecting portion may be sealed with an O-ring. The hole detection unit 10 and the air cylinder 2
1, a sensing plate 26, a proximity switch 6, a switching valve 33, and an air pressure source 31 constitute a plate pressure detecting means.

Incidentally, in FIG. 4, the hole detection unit 10,
The configurations of the air cylinder 21, the sensing plate 26, etc. are schematically shown. Next, FIGS. 5 and 6 show a work 8 applied to the device of the present invention. The work 8 shown in the figure is a door part of an automobile, and the work 8A shown in FIG. 5 is a thin plate having a hole 8a for attaching a component in the central portion as a predetermined portion. On the other hand, the work 8B of FIG. 6 shows a thick work having no holes for mounting parts at the same position where the holes 8a are provided in the work 8A.

Next, the welding condition switching operation of the apparatus of this embodiment will be described. First, as shown in FIG. 7, the work 8 is placed on the jig rotating base 7 via the bearing 9. At this time, in the case of the work 8B having no hole, the hole detection rod 13 descends against the elastic force of the coil spring 14 due to the weight of the work 8B and is held at the lower limit position as shown in FIG. 3B. It In this state, the mechanical valve 17 is in the OFF state and takes the position shown in FIG. 4, and the air pressure source 31 switches the valve.
No air pressure is supplied to 33, and the switching valve 33 assumes the position shown in FIG. As a result, the air from the air pressure source 31 is supplied to the air chamber 23 side of the air cylinder 21 via the switching valve 33, while the air in the air chamber 24 is opened to the atmosphere. Due to the supply of such air pressure, the piston 22 of the air cylinder 21 moves downward as shown by the solid line in FIG. 4, and the sensing plate 26 also moves downward as shown by the solid line in FIG. Approach. Proximity switch 6
Turns on when the sensing plate approaches. The ON signal of the proximity switch 6 is input to the controller 34. controller
When the ON signal of the proximity switch 6 is input, 34 determines that the mounted work is the work 8B without holes, and switches and sets the welding condition when the plate thickness is thick.

On the other hand, when the work 8A having the hole 8a is placed, the hole detecting rod 13 is moved by the elastic force of the coil spring 14 into the hole 8a of the work 8A as shown in FIG. 3 (A).
And is held at the upper limit position. In this state, the mechanical valve 16 is in the ON state and in the position opposite to that in FIG. 4 (the lower position in the figure), the air pressure is supplied from the air pressure source 31 to the switching valve 33 as the signal pressure, and the switching valve 33
Takes a position opposite to that in FIG. 4 (position on the left side in the figure). As a result, the air from the air pressure source 31 switches the switching valve.
While being supplied to the air chamber 24 side of the air cylinder 21 via 33, the air in the air chamber 23 is opened to the atmosphere. Due to the supply of the air pressure, the piston 22 of the air cylinder 21 moves upward as shown by the broken line in FIG. 4, and the sensing plate 26 also moves upward as shown by the broken line in FIG. Separated from 6. The proximity switch 6 is turned off due to the separation of the sensing plate. The off signal of the proximity switch 6 is input to the controller 34. When the OFF signal of the proximity switch 6 is input, the controller 34 determines that the mounted work is the work 8A having holes, and switches and sets the welding conditions when the plate thickness is thin. After the welding conditions are set, stud welding is performed at a predetermined position by a welding machine while manually rotating the jig rotating base 7, for example.

As described above, when stud welding is performed on the work 8 having or without holes at the same specific portion depending on the plate thickness, the presence or absence of the hole at the specific portion is detected by the hole detecting unit 10, and If it is configured to automatically switch and set the welding conditions according to the plate thickness based on the detection signal,
Appropriate welding conditions are automatically switched and set according to the plate thickness simply by placing the work 8, so compared with the conventional case where welding conditions are switched and set by visual confirmation of the hole 8a by the operator. As a result, erroneous setting of welding conditions can be eliminated, occurrence of welding defects due to nonconformity of welding conditions can be prevented, and quality can be improved. Further, the structure is simple and the equipment cost is low compared with the case where a device for directly measuring the plate thickness is provided, which is advantageous.

Further, the hole detection unit 10 provided in the rotating portion
Since the hole detection output by the is input to the controller 34 via the contactless proximity switch 6 provided on the fixed side, it is not necessary to provide electrical wiring between the rotating portion and the fixed portion, and the work 8 The electric wiring connecting the proximity switch 6 and the controller 34 does not get entangled with the rotating shaft 4 and the like due to the rotation of the rotating portion side on which is mounted. Further, since it is not necessary to use a brush having a problem in durability to establish an electrical connection structure between the rotating portion and the fixed portion, the durability of the welding condition switching device becomes good.

Further, since the sensing plate 26 has a ring shape, the position of the sensing plate 26 can always be detected by the proximity switch 6 regardless of the rotational position of the jig rotating base 7.

[0025]

As described above, according to the first aspect of the present invention, when stud welding is performed on a work having different hole drilling positions depending on the plate thickness, the presence or absence of holes in the work is detected to determine the plate thickness. Since it is configured to automatically judge the welding conditions,
The reliability of switching setting of welding conditions is improved as compared with the conventional method in which a hole is visually confirmed by an operator, and by setting appropriate welding conditions, occurrence of welding failure can be prevented and quality can be improved. Further, the structure is simple and the equipment cost is low compared with the case where a device for directly measuring the plate thickness is provided, which is advantageous.

According to the invention of claim 2, the presence / absence detection of the hole on the rotating portion side is converted into the moving operation of the moving body through the fluid pressure cylinder, and the position of the moving body is provided on the fixed side. Since it is configured to detect with a non-contact type proximity switch and convert it into an electric signal to the control means for setting welding conditions, the electric wiring is only on the fixed side, there is no concern that the electric wiring will be entangled in the rotating part. . Further, since electric wiring is not required between the rotating portion and the fixed portion, it is not necessary to use a brush having a problem with durability, and the durability of the welding condition switching device can be improved.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing an embodiment of a welding condition switching device of a stud welding device according to the present invention.

FIG. 2 is a plan view of a jig rotating base according to the above embodiment.

FIG. 3 is a diagram showing a hole detection unit portion of the above embodiment.

FIG. 4 is a diagram showing an air supply path of the embodiment.

[Fig. 5] Diagram of work with holes

[Figure 6] Diagram of work without holes

FIG. 7 is a diagram showing a state in which a work is placed on a jig rotating base.

[Explanation of symbols]

 2 Jig base 4 Rotation axis 6 Proximity switch 7 Jig rotation base 8 Work 8a Hole 9 Bearing 10 Hole detection unit 13 Hole detection rod 14 Coil spring 17 Mechanical valve 21 Air cylinder 25 Cylinder rod 26 Sensing plate 31 Air pressure source 32 Air supply passage 33 Switching valve 34 Controller

Claims (2)

[Claims] 1. A welding of a stud welding device adapted to switch welding conditions according to the plate thickness of the work when the stud welding is performed by positioning a work having different drilling positions depending on the plate thickness in a rotary welding jig. In the condition switching device, a plate thickness detecting means for detecting the presence or absence of a hole in the same predetermined portion of the work and a plate thickness detecting means, and a control means for switching control of welding conditions based on the detection output of the plate thickness detecting means. And a welding condition switching device for a stud welding device. 2. The plate thickness detecting means is slidably supported in a vertical direction on a work mounting rotary base of a rotary welding jig, and an elastic member is mounted when a work having a hole at the predetermined portion is mounted. Is held at the upper limit position by penetrating the hole by the elastic urging force of the elastic member, and when a work without a hole is placed on the predetermined portion, the weight of the work lowers against the elastic urging force of the elastic member to move to the lower limit position. A hole detection rod held by the piston, and two fluid pressure chambers that are vertically divided by a piston, and a fluid that is fixed to the lower surface of the rotary base with a cylinder rod that extends and contracts in conjunction with the piston facing downward. A pressure cylinder, a fluid pressure supply source connected to the two fluid pressure chambers of the fluid pressure cylinder via a fluid pressure supply passage so that the fluid pressure can be supplied, and a fluid pressure supply source fixed to the tip of the cylinder rod of the fluid pressure cylinder. A moving body that moves in the up-and-down direction as it expands and contracts, and a jig pedestal side that is fixed to a fixed part and rotatably supports the rotation axis of the rotating base, and is attached so as to face the moving body.・ Proximity switch that turns on / off according to the separation operation, and fluid pressure that selectively switches between the fluid pressure chamber that is mechanically connected to the lower end of the hole detection rod and that supplies the fluid pressure according to the lower end position of the hole detection rod. 2. The welding condition switching device for a stud welding device according to claim 1, further comprising: a supply passage switching means, which is configured to output an on / off signal of the proximity switch to the control means.