JPH0519185Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to a solid stud that can be used in stud welding, particularly in capacitor discharge type stud welding.

[Prior Art] Studs for stud welding have been known in various shapes and materials, and the shape of the stud body is formed in various ways depending on the purpose of use. The shape of the weld is usually such that a chip (protrusion) is provided at the center of the end face of the weld to help generate an arc during welding and ensure reliable and good welding.
As a result, when welding energy is supplied from the welding machine during welding, an electrical discharge occurs between the chip at the center of the tip and the base metal, an arc begins to occur, and it gradually spreads across the entire end surface of the tip. The metal on the end face is melted and welded to the base metal. Therefore, the tip at the tip of the stud plays an important role in welding.

On the other hand, the stud welding machine itself is becoming increasingly automated using robots to improve worker safety and save labor, and to widen the application of stud welding.As a result, the stud itself has changed from being manually attached to the welding machine to being automatically supplied. The method of continuously and sequentially supplying equipment is changing. This has dramatically improved the efficiency of stud welding.

In addition, in the production of this type of stud, normally a wire rod of the required thickness is cut to the required length, and each cut wire rod piece is pressed in the axial direction to form a chip at one end and a chip at the other end. The cut surface is shaped into a plane perpendicular to the axis.

[Problems to be solved by the invention] By the way, in the automation of stud welding, one method of automatically supplying studs is to make the studs continue back and forth in the axial direction and push them forward one by one using compressed air or the like. In this method, when the studs to be supplied are solid, the tip at the tip of the stud often collides with the rear end of the adjacent stud when the stud is automatically supplied using compressed air, causing the tip to be deformed or crushed. There may be cases where This tendency is particularly noticeable when the material of the solid stud itself is relatively soft, such as copper or aluminum. If the tip at the tip of the stud is deformed or crushed in this way, the required arc may not be generated between the tip and the base metal during welding, or it may be difficult to generate, and as a result, welding may be impossible or impossible. This causes welding defects.

Therefore, the purpose of the present invention is to eliminate the risk of deforming or crushing the tips of each stud until welding even when the solid studs are automatically supplied, and to substantially change the conventional stud manufacturing method as described above. An object of the present invention is to provide a solid stud for stud welding that can be manufactured without any problems.

[Means for Solving the Problems] In order to achieve the above object, in the solid stud for stud welding according to the present invention, the tip of the solid stud body to be welded to the base material is A chip is formed, and a recess is formed at the rear end of the stud body opposite to the chip, and has a depth at least equal to or greater than the height of the chip at the tip. It is configured to be able to receive the tip at the tip of the solid stud without contact.

[Example] Hereinafter, an example of the present invention will be described with reference to the drawings.

In the drawings, reference numeral 1 denotes a solid stud body, and a tip 2 is formed at the center of its tip, and the shape and size of this tip 2 can be designed as appropriate. A hemispherical recess 3 having dimensions larger than the height and diameter of the tip 2 is formed in the center of the rear end of the stud body 1. This recess 3 does not have to be hemispherical as shown in the figure, but may be formed in any shape as long as it can receive the chip 2 without contact.

Next, to briefly explain the production of solid studs according to the present invention, as in the conventional method, a wire rod having a required wire diameter is prepared, and this wire rod is cut to a length slightly longer than the length of the stud to be manufactured. Each wire rod piece thus cut is fitted into a chip mold and pressed from one end against the shaft body, thereby forming a desired chip at the tip of the wire rod piece. By using a pressing member with a convex central tip as the pressing member used in this pressing process, a required concave portion can be formed at the rear end at the same time as the chip at the tip of the wire piece is formed, and the rear end surface can also be shaped. be able to. Therefore, from a manufacturing point of view, the stud according to the invention can be made as easily or more easily than conventional solid studs.

The solid studs of the present invention constructed in this way are particularly advantageous for capacitor discharge type stud welding, and can be used even when adjacent studs come into strong contact with each other while being transported through the stud supply and mounting mechanism of an automated welding machine. The tip at the distal end of each stud is received within a recess in the rear face of the adjacent stud, avoiding the risk of deformation or crushing.

[Effects of the invention] As explained above, according to the invention, a recess having a depth at least equal to or greater than the height of the tip at the tip is formed at the rear end of the solid stud body, and this recess When the studs are sequentially pumped to the stud welding machine, they are configured so that they can receive the chips at the tips of adjacent studs without contact.
The tip at the tip of the solid stud is protected until welding, and welding can be performed reliably without worrying about welding defects or non-welding.This not only greatly improves welding work efficiency, but also eliminates wasted studs. , which is extremely useful from a cost standpoint.

[Brief explanation of the drawing]

The drawing is a schematic partial sectional view showing an embodiment of the present invention. In the figure, 1... solid stud body, 2... tip tip, 3... concave portion.

Claims (1)

[Scope of utility model registration request] A tip is formed at the tip of the solid stud body that is to be welded to the base part, and a tip is formed at the rear end of the stud body opposite to this tip to a depth at least equal to the height of the tip at the tip. A solid stud for stud welding, characterized in that a concave portion having a diameter is formed, and this concave portion is configured to receive chips at the tips of adjacent studs without contact when the studs are sequentially pumped to a stud welding machine. .