JPH0357348Y2 - - Google Patents

Description

[Detailed description of the invention] (Industrial application field) This invention is used in the technical field of spot welding.
In particular, it relates to projection welding equipment.

(Prior Art) Projection welding, in which fastening members such as bolts and nuts are electrically applied while pressurizing a base material made of a thin steel plate, has been conventionally performed. Various welding devices have been proposed to be applied to this, and one of them is a welding pin that supports the nut, which consists of a main body pin for small-diameter nuts and a cover pin attached to the main body pin. Some devices have made it possible to perform projection welding of nuts of different types (for example, see Japanese Utility Model Application Publication No. 38681/1983).

(Problems to be solved by the invention) However, although the conventional projection welding device described above enables welding of different kinds of nuts,
There are still problems to be solved in order to be able to weld bolts with this welding device.

The present invention was made to solve the above-mentioned conventional problems, and enables projection welding of fastening members such as bolts and nuts with a single welding device.

(Means for Solving the Problems) The projection welding device of the present invention is a projection welding device having a fixed electrode and a movable electrode, as a means for solving the above conventional problems. a holding member disposed between the electrode and the movable electrode and movable in a direction perpendicular to the arrangement direction of both electrodes; and a holding member provided at a predetermined interval in the moving direction of the holding member; It is characterized by having a plurality of intermediate electrodes that have electrode surfaces that are in contact with the fixed electrode and the movable electrode and can be energized, and that have a holding portion for the fastening member on the electrode surface on the movable electrode side.

(Function) In the above-mentioned configuration of the present invention, for example, in order to projection weld a nut to a base material such as a thin steel plate, the holding member is moved and one of the nut intermediate electrodes is separated into a fixed electrode and a movable electrode. The movable electrode is moved to sandwich the base material, the nut, and the intermediate electrode between the movable electrode and the fixed electrode. Welding is performed by applying current between the electrode, intermediate electrode, and fixed electrode. Next, to projection weld the bolt to the base metal, move the holding member to position one of the bolt intermediate electrodes between the fixed electrode and the movable electrode, and insert the bolt into the bolt hole in the base metal. The inserted part is held in the holding part of the intermediate electrode, and welding is then carried out in the same manner as the nut welding.

(Example) Hereinafter, an example of the present invention will be described based on FIGS. 1 to 4.

As shown in FIG. 1, the projection welding apparatus 1 of this embodiment is of a stationary type, and has a movable electrode mechanism 3, a fixed electrode mechanism 4, and an intermediate electrode mechanism 5 assembled on a frame 2. The pedestal 2 is vertical,
It has an upper arm 6 and a lower arm 7 that protrude to the front. In the movable electrode mechanism 3, a cylinder 8 is fixed downwardly on the upper surface of the tip of an upper arm 6, and a rod-shaped electrode holder 10 is attached vertically to the tip of a lifting platform 9 that is raised and lowered by the cylinder 8.
A short rod-shaped movable electrode 11 is attached to the lower end of the electrode holder 10.
is attached removably. The movable electrode 11 is
It has an electrode surface 12 on the lower end surface (see FIG. 3). In the fixed electrode mechanism 4, a support stand 13 is fixedly installed on the upper surface of the tip of the lower arm 7, and a rod-shaped electrode holder 14 is attached to the tip of the support stand 13 in a vertical direction.
A short rod-shaped fixed electrode 15 is removably attached to the upper end of the electrode holder 14. The fixed electrode 15 has an electrode surface 16 on its upper end surface (see FIG. 3). In the intermediate electrode mechanism 5, a portal-shaped support frame 17 is fixed to the tip of the lower holder 7 so as to straddle the upper part of the support base 13, and a holding member 18 is provided on the upper surface of the support frame 17. An intermediate electrode 19 for nuts and an intermediate electrode 20 for bolts are attached. As shown in FIG. 2, the holding member 18 has two holding arms 22 radially fixed to the side surface of a boss portion 21 with a fixed angle apart, and a cylindrical shape at the tip of each holding arm 22. A retaining ring 23 is fixed thereto, and the boss portion 21 is supported on the upper surface of the support frame 17 so as to be horizontally rotatable. Intermediate electrode for nut 1
9, as shown in FIG. 3, a holding fitting 25 is attached to the upper end surface of the electrode body 24. Electrode body 2
4 has a disc-shaped holding part 27 formed at the upper end of a rod-shaped shaft part 26, and has an upper electrode surface 28 and a lower electrode surface 29 on both upper and lower end surfaces, respectively. The shaft portion 26 has an insulating bushing 30 fitted on its outer peripheral surface.
It is slidably inserted into one of the retaining rings 23 via. The holding part 27 is a holding ring 23
The insulating bushing 30 is biased upward by a compression spring 31 interposed between the insulating bushing 30 and the insulating bushing 30.
The holding fitting 25 is cap-shaped and has a nut holding hole 32 in the center. The intermediate electrode 20 for bolts is
As shown in FIG. 4, the holding portion 27 of the electrode body 24
A bolt holding hole 33 is bored in the upper end surface, and an insulating bushing 34 is fitted into the bolt holding hole 33, and is supported within the other support ring 23 in the same manner as the nut intermediate electrode 19. ing.

Next, the projection welding device 1 having the above configuration
, connect the hexagonal nut 35 and bolt 36 to the base material 3.
The welding method will be explained in step 7. The hexagonal nut 35 and the bolt 36 have protrusions (not shown) formed in advance at the joints with the base material 37. The base material 37 is a steel plate or the like, and a through hole 38 is provided at each welding location.
has. First, by rotating the holding member 18, the nut intermediate electrode 19 is connected to the movable electrode 11 and the fixed electrode 15.
The hexagonal nut 35 is held in the nut holding hole 32, and the base material 37 is placed on the hexagonal nut 35.
The through holes 38 are overlapped. The cylinder 8 is operated by the electromagnetic valve 39, and the movable electrode 11 is lowered.
The movable electrode 11 has an electrode surface 12 in contact with the base material 37, and the intermediate electrode 19 for a nut against the compression spring 31.
Press down and place the lower electrode surface 29 on the fixed electrode 15.
is brought into contact with the electrode surface 16 of the cylinder 8 and pressurized by the cylinder 8. Turn on the switch 40 and each electrode 11, 19,
15, turn on the power. Thus, hexagonal nut 35
is caused by the resistance heat of the relatively small protrusion.
Welded to 7. Therefore, the movable electrode 11 is raised and the base material 37 is attached to the nut intermediate electrode 19.
Remove from. Next, the holding member 18 is rotated to position the bolt intermediate electrode 20 between the movable electrode 11 and the fixed electrode 15, the base material 37 is placed on the upper electrode surface 28, and the male threaded portion of the bolt 36 is inserted into the base material. material 37
The bolt is inserted into the bolt holding hole 33 through the through hole 38 and held. Thereafter, as in the case of nut welding,
The movable electrode 11 is lowered to bring its electrode surface 12 into contact with the head of the bolt 36, and the fixed electrode 1
The movable electrode 1 is brought into contact with the lower electrode surface 29 of the intermediate bolt electrode 20 and the electrode surface 16 of the
1. Electricity is applied between the bolt intermediate electrode 20 and the fixed electrode 15 to weld the bolt 36 to the base material 37.
Finally, the movable electrode 11 is raised and the base material 37 is removed from the bolt intermediate electrode 20 to complete the welding work.

The nut intermediate electrode 19 was used for the hexagonal nut 35, but as another embodiment, one for the T-nut 41 is shown in FIGS. 5 and 6. The nut intermediate electrode 42 shown in FIG. 5 includes an electrode body 24 and a holding fitting 43. As shown in FIG. The electrode main body 24 has a tapered hole 44 and a cylindrical hole 45 formed inwardly from the upper end surface in the center of the holding part 27, and a support ring is formed in the same manner as the nut intermediate electrode 19. 23. The holding fitting 43 has a head 47 formed at the upper end of a cylindrical portion 46 having an outer peripheral tapered surface that fits into the tapered hole 44.
A guide pin 48 is slidably inserted into the center hole of the cylindrical hole 45, and a compression spring 49 is interposed in the hollow hole of the cylindrical portion 46 between the guide pin 48 and the bottom of the cylindrical hole 45. The head 47 has an upper electrode surface 50 on its upper end surface, and the compression spring 49 biases and supports the guide pin 48 upward. In order to weld the T-nut 41 using this intermediate nut electrode 42, the flange portion of the T-nut 41 is placed on the base material 37 placed on the upper electrode surface 50, and the guide pin 48 is inserted through the through hole 38 of the base material 37. Insert into the female threaded portion of the T-nut 41. The movable electrode 11 is lowered, and the electrode surface 12 is attached to the T-nut 4.
Abut against the flange of No.1. At this time, the female threaded portion of the T-nut 41 enters into the escape hole 51 bored in the electrode surface 12. The movable electrode 11 pushes down the nut intermediate electrode 42 via the holding fitting 43,
The lower electrode surface 29 is connected to the electrode surface 16 of the fixed electrode 15.
is brought into contact with the cylinder 8 and pressurized by the cylinder 8. When electricity is applied between the movable electrode 11, the nut intermediate electrode 42, and the fixed electrode 15, the T-nut 41 is welded to the base material 37. Further, the nut intermediate electrode 52 shown in FIG.
A nut holding hole 53 is formed in the upper end surface of the nut holding hole 53, and an insulating bushing 54 is fitted into the nut holding hole 53, and is supported within the support ring 23 in the same manner as the nut intermediate electrode 19. To weld the T-nut 41 using this nut intermediate electrode 52, place the base metal 37 on the upper electrode surface 28, and insert the female threaded portion of the T-nut 41 into the nut holding hole 53 through the through hole 38 of the base metal 37. and hold it. Thereafter, as in the case of bolt welding, the movable electrode 11 is lowered, its electrode surface 12 is brought into contact with the flange portion of the T-nut 41 and pressure is applied, and the fixed electrode 1
The lower electrode surface 29 of the nut intermediate electrode 52 is brought into contact with the electrode surface 16 of the nut 5, and electricity is applied between the movable electrode 11, the nut intermediate electrode 52, and the fixed electrode 15.
The nut 41 is welded to the base metal 37.

Note that in the holding member 18 of this embodiment, the holding arm
Although the number of intermediate electrodes 22 is two, it is also possible to form them into a disk shape and arrange retaining rings 23 at equally spaced positions on the outer periphery, thereby increasing the types and number of intermediate electrodes. This makes it possible to weld several types of fastening members of different types and sizes with one projection welding device.

(Effects of the Invention) Since the present invention has the above-described configuration, it is possible to weld many types of fastening members of different types and sizes with one projection welding device. Therefore, it has excellent advantages such as reduced equipment costs and improved productivity.

[Brief explanation of the drawing]

The drawings illustrate embodiments of the present invention, in which Fig. 1 is a perspective view of the external appearance of a projection welding device, Fig. 2 is a plan view of a holding member, Fig. 3 is a central longitudinal sectional view of an intermediate electrode for a nut, and Fig. FIG. 4 is a central vertical cross-sectional view of the intermediate electrode for a bolt, and FIGS. 5 and 6 are central vertical cross-sectional views of other embodiments of the intermediate electrode for a nut, respectively. DESCRIPTION OF SYMBOLS 1... Projection welding device, 11... Movable electrode, 15... Fixed electrode, 18... Holding member,
19... Intermediate electrode for nut, 20... Intermediate electrode for bolt, 27... Holding part, 28... Upper electrode surface,
29... Lower electrode surface, 42... Intermediate electrode for nut, 52... Intermediate electrode for nut.

Claims (1)

[Scope of utility model registration request] A projection welding device having a fixed electrode and a movable electrode includes a holding member disposed between the fixed electrode and the movable electrode and movable in a direction perpendicular to the arrangement direction of both electrodes; A plurality of electrode surfaces are provided on the holding member at predetermined intervals in the direction of movement thereof, and have electrode surfaces that contact the fixed electrode and the movable electrode and can be energized, and have a holding portion for the fastening member on the electrode surface on the movable electrode side. A projection welding device characterized by comprising: a plurality of intermediate electrodes.