JPS6245826Y2 - - Google Patents

Description

[Detailed description of the invention] (Industrial application field) The present invention is applicable to seam welding of an object to be welded consisting of a main body and a lid, such as a gasoline tank, etc.
The present invention relates to a workpiece guiding device for a seam welding machine that automatically guides the workpiece along a welding line of the workpiece.

(Prior Art) Conventionally, a welding object guiding device for a seam welding machine includes a guide rail that is attached to a seam welding machine body having an upper electrode and a lower electrode, and has a ratchet attached to the upper part so as to be retractable, and a guide rail for guiding the seam welding machine. a rotary table movably and rotatably supported by the machine body and formed in a shape suitable for the welding line consisting of a straight part and a circular arc part of the workpiece; a copying plate that engages with and guides the straight portion of the welding line; and a copying plate that is attached to the rotation table at a position corresponding to the center of the circular arc portion of the welding line that engages with the guide rail to guide the welding line. The object to be welded is placed on the rotary table, positioned and fixed, the object to be welded is held between the upper electrode and the lower electrode, and then There is a welding method in which the object to be welded is guided along the welding line while being energized and pressurized by both electrodes.

A welding workpiece guidance device for welding workpieces in which all arcuate radii of the welding lines are equal is disclosed in Japanese Patent Application No. 48-32489 (Japanese Patent Publication No. 52-22746).
Japanese Patent Application No. 50-15691 (Japanese Patent Publication No. 54-3012) discloses a welding object guiding device for welding objects whose welding lines have different arcuate radii.
has been disclosed.

However, in all of the above-mentioned devices, a hole is provided in the upper part of the guide rail, the ratchet main body is inserted into the hole so as to be freely retractable, and the ratchet is constantly biased upward by a spring. For this reason, there is no problem with internal water-cooled seam welding machines, but with external water-cooled seam welding machines, seam welding is performed while cooling water is applied from the outside.
The small gap between the perforation and the ratchet body allows the cooling water and foreign matter mixed with the cooling water, such as spatter and electrode chips, to easily enter the perforation. If a foreign object enters the borehole in this way, when the ratchet body is pushed down by the copying plate, cooling water will fill the borehole and the ratchet body will not descend immediately, or the foreign matter will be drawn into the gap between the borehole and the ratchet body. Problems such as interfering with the protruding and retracting movement of the ratchet main body occur, resulting in a significant deterioration of welding quality.

(Purpose of the invention) An object of the invention is to provide a workpiece guidance device for a seam welder that eliminates the above-mentioned problems and allows extremely good seam welding from the viewpoint of improving welding quality.

(Structure of the invention) Therefore, the structure of the invention is to form a hole in the upper surface of the guide rail for guiding the workpiece provided in the main body of the seam welding machine, to insert the ratchet into the hole so as to be able to come out and go, and to insert the ratchet into the bottom of the hole. This device is characterized in that a fluid supply path is formed in communication with the side so that fluid can be supplied upward from the inside of the perforation to the gap between the perforation and the ratchet.

(Function) With this configuration, even if foreign substances such as cooling water, spatter, and electrode chips try to enter through the gap between the perforation and the ratchet, fluid is supplied from the inside of the perforation toward the gap, thereby blocking the gap. A curtain of fluid can be formed to reliably prevent foreign matter from entering. Therefore, the ratchet always appears and disappears quickly, and the workpiece can be smoothly guided along the weld line of the workpiece, thereby preventing welding defects.

(Example) An example of the present invention will be described below.
FIG. 1 is a side view of this embodiment, and FIG. 2 is a plan view of the main part thereof. In both figures, 1 is a seam welding machine main body, and as shown in FIG. 2, brackets 2 and 3 are fixed to the seam welding machine main body 1 in parallel with each other in the horizontal direction. As shown in FIG. 1, a pair of brackets 4 and 5 are fixed to the bracket 2 side of the seam welding machine main body 1, and 6 is attached to the seam welding machine main body 1.
This is a jig that is movably attached to the A link arm 8 is connected to the pair of brackets 4 and 5 via a pin 7 so as to be rotatable in the horizontal direction, and further includes:
A link arm 10 is connected to the link arm 8 via a pin 9 so as to be rotatable in the horizontal direction.

Reference numeral 11 denotes a rotary table that is rotatably supported on the upper part of the link arm 10 and is formed to match the shape of the welding line of the workpiece. is rotary table 11
Multiple floating mechanisms 1 attached to appropriate locations
Supported by 3. The floating mechanism 13 includes a guide pin 14 whose upper end is fixed to the pedestal 12, and a casing 15 that is attached to the rotary table 11 and fits and holds the guide pin 14 vertically movably through a pair of bearings (not shown). , a spring 16 that is mounted on the upper side of the guide pin 14 and always urges the pedestal 12 upward;
The stopper 17 is fixedly attached to the lower end of the rotary table 11 and engages with the casing 15 to suppress the amount of upward movement of the pedestal 12 with respect to the rotary table 11.

At an appropriate height of the seam welding body 1,
An upper electrode 18 and a lower electrode 19 are each rotatably arranged. The upper electrode 18 is provided movably in the AA' direction by a pressurizing cylinder device (not shown), and the lower electrode 19 is directly connected to a rotational drive source (not shown) and fixed to a bracket (not shown). .

Note that even if the welded parts of the workpieces W, W' placed on the pedestal 12 descend in the direction A' in FIG. 1 due to frictional wear between the upper electrode 18 and the lower electrode 19, the Since the pedestal 12 is elastically supported by the floating mechanism 13, the pedestal 12 can quickly follow the downward movement of the welded portion.

Reference numeral 20 denotes an arm fixed at a proper position on the link arm 10. The upper end of the arm 20 extends to a height above the upper electrode 18, and the horizontal portion of the upper end side of the arm 20 is connected to the center line of the rotary table 11. A hollow bracket 21 extending vertically in accordance with
is fixed. A clamp member 22 for holding the workpiece W to be welded is fitted into the bracket 21 so as to be movable up and down. ing.

Reference numeral 24 denotes a guide rail for guiding the straight part of the weld line of the objects to be welded W, W', and is fixed horizontally to the tips of the brackets 2, 3. FIG. 3 is an enlarged front view of the guide rail 24. A cam stopper 25 having an arcuate portion 25a is provided at an appropriate position on the guide rail 24, and the arcuate portion 25a is formed to match the arc of a half-moon cam pin 34, which will be described later. has been done. 26 is a guide groove formed in the guide rail.

As shown in FIG. 4, a plurality of stepped holes 27 are formed on the upper surface side of the guide rail 24, and each hole 27 has an inclined surface 28a and a vertical surface 28.
A ratchet 28 having a shape b is inserted so as to be retractable. A spring 29 is installed between the ratchet 28 and the bottom of the perforation 27 to constantly bias the ratchet 28 upward. An air supply path (fluid supply path) 30 is formed on the bottom side of the perforation 27 and communicates with the perforation 27, and the air supply path 30 is connected and communicated with an air supply source (fluid supply source) not shown. 31 is a holding plate for preventing the ratchet 28 from coming off from the perforation 27, and 32 is a bush.

Therefore, the ratchet 28 is urged upward not only by the spring 29 but also by compressed air supplied from the air supply source into the borehole 27 via the air supply path 30. becomes. Therefore, the spring 29 may be removed and the ratchet 28 may be levitated by the biasing force of the air spring using only compressed air.

Reference numeral 33 denotes a copying plate for engaging with the vertical surface 28b of the ratchet 28 to guide the straight part of the welding line of the objects to be welded W, W', and is fixed to the straight part of the outer periphery of the rotary table 11. . Reference numeral 34 denotes a half-moon cam pin that engages with a cam stopper 25 provided on the guide rail 24 to guide the arc portion of the weld line of the workpieces W, W', and is located at the center of the arc portion of the weld line of the rotary table 11. It is fixedly attached to. The half-moon pin 34 is positioned and fixed on the rotary table 11 so that the vertical surface of the U-shaped cam groove 34a (see FIG. 4) formed in the half-moon cam pin 34 is parallel to the straight section to be welded next. has been done.

The operation of the thus configured workpiece guiding device will be described. First, the workpieces W, W' are placed on the support 12, and the clamp cylinder device 23
The clamp member 22 clamps the workpiece W,
W' is securely clamped. And the upper electrode 1
8 and the lower electrode 19 are in an open state (upper electrode 18
When a pressure cylinder device (not shown) attached to the upper part of the seam welding machine body 1 is turned on, the upper electrode 18 descends and the welded parts of the workpieces W, W' are clamped between the upper electrode 18 and the lower electrode 19. At the same time, compressed air is supplied from the air supply source through the air supply path 30 to the perforations 2.
7, and the compressed air supplied into the bore 27 penetrates the bore 27, the ratchet 28 and the bush 32.
The water rises through the small gap between the hole 27 and the outside of the hole 27 and gushes out.

Therefore, the electrodes 18 and 19 are rotated and energized and pressurized to supply cooling water from the outside to the workpiece W.
While pouring it into the welded part of W', seam welding of the welded parts of the objects to be welded W and W' is performed. In FIG. 2, when welding of the straight parts of the weld lines of the objects W, W' is completed, the half-moon cam pin 34, which guides the arcuate part to be welded next, pushes down and passes through an auxiliary ratchet (not shown), and the guide It abuts against the arcuate portion 25a of the cam stopper 25 provided on the rail 24.

When the half-moon cam pin 34 comes into contact with the arcuate portion 25a of the cam stopper 25, the auxiliary ratchet rises and supports the half-moon cam pin 34 from behind, and the half-moon cam pin 34 at that position closes in the U-shape formed on the half-moon cam pin 34. The cam groove 34a rotates to a rotational position where it engages with the cam stopper 25. That is, the half-moon cam pin 34 serves as the center of rotation to weld the arc portions of the welding lines of the objects to be welded W, W'.

As the welding of the arcuate portions of the workpieces W, W' progresses, the tracing plate 33 that guides the straight portion to be welded next moves along the inclined surface 2 formed on the ratchet 28.
8a, and then the elastic force of the spring 29 and the air pressure (if the spring 29 is not interposed, only the air pressure. The same applies hereinafter).
The ratchet 28 is gradually pushed down against the pressure, and at the same time when all the welding of the arc portion is completed, the copying plate 33 passes the ratchet 28, and the ratchet 28 is raised by the elastic force of the spring 29 and air pressure. , then the tracing plate 33 is moved to the ratchet 28
The straight portions of the welding lines of the objects W and W' are smoothly guided by making surface contact with the vertical surfaces 28b of the welding parts W and W'.

Thereafter, welding of the linear portions and arcuate portions of the objects W, W' to be welded is performed one after another in this manner, and one welding cycle ends when all welding is completed.

Here, cooling water applied to the welding part during the welding cycle, welding spatter, both the electrodes 18 and 19
(The electrodes 18 and 19 are shaped with a shaping tool (not shown) during welding.) Foreign matter such as chips may enter through the perforation 27 formed in the guide rail 24 and the small gap between the ratchet 28 and the bush 32. However, as mentioned above, the hole 27 is inserted through the gap.
Since compressed air is constantly ejected to the outside of the hole 27, a strong air curtain is formed and foreign matter is reliably prevented from entering the perforation 27.

(Effects of the invention) As described above, according to the invention, the structure is such that fluid can be constantly ejected from the small gap between the perforation and the ratchet, so even if it is an external water-cooled seam welding machine, cooling water can be This ensures that foreign objects such as spatter, electrode chips, etc. are prevented from entering the borehole through the small gap between the borehole and the ratchet.
As a result, the ratchet always moves smoothly and quickly, guiding the workpiece accurately along the welding line, preventing welding defects, improving welding quality, and reducing costs. effective.

[Brief explanation of the drawing]

FIG. 1 is a schematic side view showing an embodiment of the present invention;
Figure 2 is a schematic plan view of Figure 1, Figure 3 is an enlarged front view of the guide rail in Figure 1, and Figure 4 is an enlarged view of the engaged state of the half-moon cam pin and cam stopper in Figure 1. FIG. 1... Seam welding machine main body, 2... Rotating table, 18... Upper electrode, 19... Lower electrode, 24
...Guide rail, 25...Cam stop stop, 25
a...Circular arc portion, 27...Perforation, 28...Ratchet, 30...Air supply path (fluid supply path), 34...
...Half-moon cam pin, W, W'...Object to be welded.

Claims (1)

[Scope of utility model registration request] The work to be welded is held between the upper electrode and the lower electrode,
In the seam welding machine that welds the workpiece while energizing and pressurizing the workpiece with both electrodes, a perforation is formed in the upper surface of a guide rail provided in the seam welding machine body for guiding the workpiece. 1. A welding object guiding device for a seam welding machine, characterized in that a ratchet is inserted into and retracted from the perforation, and a fluid supply passage is formed in communication with the bottom side of the perforation.