JPS5836455Y2 - Electrode device for resistance welding - Google Patents

Description

[Detailed description of the invention] This invention is a resistance welding electrode device used for in-process inspection of resistance spot welds using ultrasonic waves. It is called an electrode.

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This in-process inspection using ultrasonic waves involves attaching an ultrasonic vibrator to one of the pair of electrodes used in resistance spot welding, and using the ultrasonic waves transmitted from the ultrasonic vibrator during welding to join the objects to be welded. This is a way to know the condition.

The ultrasonic waves transmitted from the ultrasonic transducer pass through the object to be welded, are reflected by the ultrasonic reflecting surface provided in the counter electrode, pass through the object again, and are received by the ultrasonic transducer. be done.

Since the received ultrasonic waves pass through the object to be welded twice, changes in the physical properties of the object to be welded due to temperature rise are well captured, and therefore the welding state can be determined from the amount of change in the received ultrasonic waves. I can do it.

First, a conventional welding electrode for reflecting ultrasonic waves will be explained.

FIG. 1 shows a conventional welding electrode for reflecting ultrasonic waves that is integrally formed.

In FIG. 1, 1 is the electrode tip surface in contact with the object to be welded 5;
2 is a flat ultrasonic reflecting surface for reflecting ultrasonic waves transmitted from an ultrasonic transducer 6 to the ultrasonic transducer 6 side, 3 is a water cooling hole, and 4 is a welding electrode for reflecting ultrasonic waves. A tapered part for fitting into an electrode holder (not shown), 5 is a welded object, 6 is an ultrasonic vibrator for transmitting and receiving ultrasonic waves, and 7 is a welding device with an ultrasonic vibrator that incorporates the ultrasonic vibrator 6. It is an electrode.

As described above, in the conventional device, the bottom of the water cooling hole 3 is processed into a flat surface and used as the ultrasonic reflecting surface 2.

Incidentally, the ultrasonic waves emitted from the ultrasonic transducer 6 travel straight in the near field, and diffuse at a certain directivity angle in the far field.

Therefore, in the conventional method, the ultrasonic waves reflected by the ultrasonic reflecting surface 2 are diffused, the density of the ultrasonic waves passing through the joint decreases, and the decomposition performance for identifying the size of the joint decreases. This inspection method cannot be applied when the diameter of the joint is small, such as when welding objects to be welded.

This idea was made to improve the drawbacks of the conventional ones. By making the ultrasonic reflecting surface 2 spherical, the decomposition performance is high, and it is also suitable for inspecting the joint state of thin objects to be welded. The object is to provide an applicable electrode device for resistance welding.

Examples of this invention will be described below.

In FIG. 2, the same reference numerals as in FIG. 1 indicate the same or corresponding parts.

Reference numeral 8 denotes a cap having an electrode tip surface 1 in contact with the object to be welded 5 on one side, and an ultrasonic reflecting surface 2 for reflecting ultrasonic waves on the other side.The ultrasonic reflecting surface 2 focuses the reflected ultrasonic waves. It is machined into a spherical shape.

A body 9 has a water cooling hole 3 and a tapered part 10 for attaching the chip 8 therein, and has a tapered part 4 on its outer periphery for fitting into an electrode holder (not shown).

6 is an ultrasonic vibrator, and 7 is a welding electrode with an ultrasonic vibrator.

As described above, in the ultrasonic reflecting welding electrode device according to this invention, since the ultrasonic reflecting surface 2 is spherical, the ultrasonic waves reflected by the ultrasonic reflecting surface 2 are focused and The density of ultrasound waves passing through the joint increases.

Therefore, the disassembly performance is improved and it can be applied to inspection of joints of thin objects to be welded.

The ultrasonic reflecting surface 2 may be used by machining the bottom of the water cooling hole 3 into a spherical surface like a conventional integrated ultrasonic reflecting welding electrode, but in this case machining becomes difficult.

The embodiment of this invention consists of a cap 8 and a body 9.
Since the cap is chip-shaped and made of a body object, one surface of the cap 8 can be processed into a spherical surface and used as the ultrasonic reflecting surface 2, and the processing of the ultrasonic reflecting surface 2 becomes easy.

Furthermore, since the cap 8 and the body 9 are removable, if the electrode tip surface 1 is deformed or worn out due to welding, only the cap 8 needs to be replaced, which is economical.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing a conventional integrated welding electrode for reflecting ultrasonic waves, and FIG. 2 is a sectional view of a welding electrode device for reflecting ultrasonic waves showing an embodiment of this invention. In the figure, 1 is the electrode tip surface, 2 is the ultrasonic reflecting surface, 3 is the water cooling hole, 4 is the tapered part for fitting the ultrasonic reflecting welding electrode into the electrode holder, 5 is the object to be welded, and 6 is the ultrasonic wave A vibrator, 7 a welding electrode with an ultrasonic vibrator, 8 a cap, 9 a body, and 110 a tapered portion for fitting the cap into the body. In addition, the same or equivalent parts in the figures are given the same reference numerals.

Claims (2)

[Scope of utility model registration request] (1) An ultrasonic transducer is attached to one of a pair of electrodes in resistance spot welding, an ultrasonic reflecting surface is provided to the other electrode, and the ultrasonic transducer transmits ultrasonic waves through the object to be welded, and It is used to inspect the bonding state by reflecting the ultrasonic waves on a sound wave reflecting surface and transmitting and receiving them, and changes in the received ultrasonic waves. An electrode device for resistance welding, characterized in that reflected ultrasonic waves are focused by doing so. (2) The resistance welding electrode device according to claim 1, wherein the other electrode having an ultrasonic reflecting surface is composed of two members.