JPH08313497A - Joining device - Google Patents

Abstract

(57) [Abstract] [Purpose] It is an object of the present invention to provide a joining device which enables direct observation of the joining state of objects to be joined and enables reliable joining. According to the above joining apparatus, an ultrasonic oscillator 21 is attached to one end face of the objects 1, 2 to be joined by heating the contact interface 3, and an ultrasonic pulse from the ultrasonic oscillator 21. To emit ultrasonic pulses to the objects to be joined 1 and 2, and the ultrasonic pulses incident to the objects 1 and 2 to be joined are
An ultrasonic flaw detector 22 is provided for observing the bonding state of the contact interface 3 and the occurrence of cracks in the objects to be bonded 1 and 2 by analyzing the waveform of the echo reflected at the contact interface 3. .

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bonding apparatus for bonding contact interfaces of objects to be bonded by local heating by microwaves or the like. The present invention relates to a joining device for observing a joining state and cracks.

[0002]

2. Description of the Related Art Conventionally, for example, when observing the bonding state of a contact interface in a bonding apparatus that arranges the contact interfaces of two objects to be bonded in a cavity and bonds the contact interfaces of the objects by local heating with microwave A means for adjusting the output of the microwave is employed so that the temperature of the contact interface of the objects to be joined is measured by an infrared temperature measuring device so that the joining of the contact interface of the objects to be joined is reliably performed.

[0003]

According to the above-mentioned conventional bonding apparatus, when observing the bonding state of the contact interface between two objects to be bonded, the temperature of the bonding portion is indirectly measured by an infrared type temperature measuring device. It is extremely difficult to directly observe whether or not the contact interface between the two objects to be joined is surely and with high quality, because such an observing means is adopted. Therefore, in the present invention, a joining device capable of directly observing the joining state of two objects to be joined by observing the echo of the ultrasonic pulse or the transmission waveform of the ultrasonic pulse and further observing the occurrence of cracks in the objects to be joined It is an issue to be solved to provide.

[0004]

According to the present invention, as a first means for solving the above-mentioned problems, a joining device for heating and joining a contact interface of a body to be joined is provided with one end of the body to be joined. An ultrasonic transducer attached to the part, an ultrasonic pulse generator for emitting an ultrasonic pulse from the ultrasonic transducer to make the ultrasonic pulse enter the object to be joined, and an ultrasonic pulse generator to the object to be joined The ultrasonic pulse is provided with an observation unit for observing the joining state of the contact interface and the occurrence of cracks in the joined object by analyzing the waveform of echo reflected at the contact interface of the joined object. It is to make a structure.

As a second means for solving the above-mentioned problems, a joining device for heating and joining the contact interface of the objects to be joined is provided so as to face both end surfaces of the object to be joined with the contact interface as the center. An ultrasonic transducer attached to the ultrasonic transducer, an ultrasonic pulse generator that emits an ultrasonic pulse from one of the ultrasonic transducers to make the ultrasonic pulse enter the object to be joined, and the ultrasonic element to the object to be joined. The incident ultrasonic pulse is analyzed by analyzing the waveform of the ultrasonic pulse received by the ultrasonic oscillator on the opposite side of the ultrasonic oscillator that emitted the ultrasonic pulse, and And a observing section for observing the occurrence of cracks in the bonded body.

As a third means for solving the above-mentioned problems, a joining device for heating and joining a contact interface of an article to be joined is formed of a material having elastic characteristics similar to those of the article to be joined. In the state where one end surface is attached to the end surface of the object to be joined, an ultrasonic transmission member that guides an ultrasonic pulse to the object to be joined, and elastic characteristics similar to those of the ultrasonic transmission member are provided. Having an adhesive for adhering one end face of the ultrasonic transmission member and the end face of the object to be joined, an ultrasonic transducer attached to the other end face of the ultrasonic transmission member, An ultrasonic pulse generator that causes an ultrasonic pulse to enter the object to be joined from the ultrasonic transducer through the ultrasonic transmission member, and an ultrasonic pulse incident to the object to be joined at the contact interface of the object. By analyzing the reflected echo waveform, The bonding state of the contact interface, and to a configuration in which a viewing unit for observing the occurrence of a crack in the object to be bonded.

As a fourth means for solving the above-mentioned problems, a joining device for heating and joining a contact interface of an article to be joined is made of a material having elastic characteristics similar to those of the article to be joined. The first and second ultrasonic transmission members for passing ultrasonic pulses, and the first and second end surfaces thereof, with one end surface being in contact with the end surfaces of the respective objects to be joined.
An adhesive having elastic characteristics similar to those of the ultrasonic transmission member, and for adhering the end surfaces of the first and second ultrasonic transmission members to the end surfaces of the respective objects to be joined, The first and second ultrasonic transducers attached to the respective end surfaces of the first and second ultrasonic transmission members, and the first ultrasonic transducer through the first ultrasonic transmission member. An ultrasonic pulse generator that causes an ultrasonic pulse to enter the object to be joined and an ultrasonic pulse that has entered the object to be joined are received by a second ultrasonic transducer via the second ultrasonic transmission member. And an observation unit for observing the joining state of the contact interface and the occurrence of cracks in the article to be joined by analyzing the waveform of the generated ultrasonic pulse.

[0008]

According to the bonding apparatus of the first aspect of the invention, the ultrasonic pulse is generated from the ultrasonic pulse generator in the process of bonding at the contact interface, and the ultrasonic pulse is incident on the object to be bonded from the ultrasonic vibrator. Then, the ultrasonic pulse is reflected by both end surfaces and contact interfaces of the objects to be joined, and becomes an echo to vibrate the ultrasonic vibrator. Therefore, the echo-corresponding signal output from the ultrasonic vibrator is changed. It is input to the observation section and analyzed,
When the eco-corresponding waveform is displayed, it is judged that the contact interface of the joined object is completely joined due to the disappearance of the eco-waveform from the contact interface. Further, by analyzing the eco-corresponding waveform, it is possible to detect the occurrence of cracks due to heating of the objects to be joined.

Further, according to the bonding apparatus of the second aspect, an ultrasonic pulse is generated from the ultrasonic pulse generator in the process of bonding at the contact interface, and an ultrasonic wave is ultrasonically generated from one ultrasonic vibrator to the object to be bonded. When the ultrasonic pulse is incident, the ultrasonic pulse transmitted through the contact interface is received by the other ultrasonic transducer attached to the other end face of the joined object, and therefore, in the observation unit,
The waveform of the ultrasonic pulse transmitted through the contact interface is analyzed, and the waveform of the ultrasonic pulse is displayed. Therefore, as the strength of the ultrasonic pulse transmitted through the contact interface increases, it is determined that the joining state of the contact interface of the object to be joined has progressed, and when the contact interface of the object to be joined is completely joined, the contact interface The intensity of the ultrasonic pulse transmitted through is maximum. Further, by analyzing the waveform of the ultrasonic pulse transmitted through the contact interface, it is possible to detect the occurrence of cracks accompanying the heating of the objects to be joined.

Further, according to the bonding apparatus of the third aspect, an ultrasonic pulse is generated from the ultrasonic pulse generator during the process of bonding at the contact interface, and the ultrasonic pulse is generated from the ultrasonic vibrator via the ultrasonic transmission member. When an ultrasonic pulse is incident on the object to be bonded, the ultrasonic pulse is reflected by both end surfaces of the object to be bonded and the contact interface, and becomes an echo to vibrate the ultrasonic vibrator. The eco-corresponding signal output from is input to the observation unit and analyzed, and the eco-corresponding waveform is displayed. Therefore, it is determined that the contact interface of the objects to be joined is completely joined due to the disappearance of the echo waveform from the contact interface. Also, by analyzing the eco-compatible waveform,
It is possible to detect the occurrence of cracks due to the heating of the objects to be joined.

Further, according to the bonding apparatus of the fourth aspect, an ultrasonic pulse is generated from the ultrasonic pulse generation unit in the process of bonding at the contact interface, and the first ultrasonic transducer generates the first ultrasonic wave. When an ultrasonic pulse is incident on the object to be joined via the sound wave transmitting member, the ultrasonic pulse transmitted through the contact interface passes through the object to be joined and the second ultrasonic wave transmitting member to the second ultrasonic wave transmitting member. Since it is received by the second ultrasonic transducer attached to the end face of, the observation unit analyzes the waveform of the ultrasonic pulse transmitted through the contact interface and displays the waveform of the ultrasonic pulse. Therefore, as the strength of the ultrasonic pulse transmitted through the contact interface increases, it is determined that the joining state of the contact interface of the object to be joined has progressed, and when the contact interface of the object to be joined is completely joined, the contact interface The intensity of the ultrasonic pulse transmitted through is maximum. Further, by analyzing the waveform of the ultrasonic pulse transmitted through the contact interface, it is possible to detect the occurrence of cracks accompanying the heating of the objects to be joined.

[0012]

Embodiments of the present invention will now be described with reference to the drawings. FIG. 1 is a block diagram showing the overall configuration of the first embodiment of the present invention. As shown in FIG. 1, in the bonding apparatus of the first embodiment, a contact interface 3 where the end faces of two rod-shaped objects to be bonded 1 and 2 are butted is arranged in the center of a cavity 4 as a bonding surface. There is. Further, the end portions of the objects to be joined 1 and 2 are held by holding portions 5 and 6. In the holding section 5, the end of the article 1 to be joined is held by the holding jig 7, and in the holding section 6, the end of the article 2 to be joined is the holding jig 8.
Is held in.

A pressurizing spring 9 is pressed against the end surface of the article 1 to be joined, and the pressurizing spring 9 can adjust the pressure applied to the end surface of the article 1 to be joined by a pressurizing screw 10. On the other hand, a pressure spring 11,
12, the pressing spring 11 is pressed against the pressing screw 1.
3, the pressing force applied to the end surface of the holding jig 8 can be adjusted, and the pressing spring 12 can adjust the pressing force applied to the end surface of the holding jig 8 by the pressing screw 14. There is. Therefore, the objects to be joined 1, 2
The bonding pressure at the contact interface 3 of the
It is possible to set variously by adjusting 3,14.

The above-mentioned cavity 4 efficiently introduces the microwave generated by the microwave generator 15 through the waveguide 16 and internally resonates it, so that the contact interfaces of the objects to be joined 1 and 2 are efficiently joined. It is constructed so that three parts can be heated and joined together. Therefore, the tuning plate 17 is provided in the cavity 4.
By adjusting the position of, microwave resonance is possible. In order to precisely adjust the position of the tuning plate 17, there is provided a fine tuning mechanism 19 mainly for the screw 18. A shield body 20 for shielding microwaves is provided in the vicinity of the fine movement mechanism 19 for tuning.

An ultrasonic transducer 21 is attached to the end surface of the article to be joined 2, and the ultrasonic transducer 21 is an ultrasonic flaw detector 2.
2 are electrically connected. This ultrasonic flaw detector 22
Oscillates a single-mode ultrasonic pulse from the ultrasonic transducer 21 and causes the ultrasonic pulse to enter the objects to be joined 1, 2, and the ultrasonic pulse is applied to both ends of the objects 1, 2 to be joined. The ultrasonic transducer 21 is reflected by the parts and the contact interface 3 and becomes eco-friendly.
Vibrate. As the ultrasonic vibrator 21 is vibrated by the echo, a voltage signal according to the strength of the echo is output from the ultrasonic vibrator 21, so the ultrasonic flaw detector 22
Analyzes the waveform based on the voltage signal output from the ultrasonic transducer 21, and causes the oscilloscope 23 to display the waveform of the echo reflected at the end of the article 1 and the contact interface 3.

The ultrasonic flaw detector 22 has a controller 24 for controlling the output of the microwave generator 15 described above.
Is electrically connected to. The controller 24 can arbitrarily set the output of the microwave generator 15, and controls the output of the microwave generator 15 based on the control signal output from the ultrasonic flaw detector 22. You can Therefore, in the state where the contact interface 3 of the objects to be joined 1 and 2 is heated by the microwave and joined, if the waveform of the echo reflected at the contact interface 3 disappears as described later, the contact interface 3 Is completely bonded, the control signal output from the ultrasonic flaw detector 22 is controlled, and the output of the microwave generator 15 is controlled to be small. The ultrasonic flaw detector 22 detects a crack generated as the bonded bodies 1 and 2 are heated by analyzing the waveform based on the voltage signal output from the ultrasonic transducer 21. be able to. This crack detection is also possible in the second, third and fourth embodiments described later.

FIG. 2 shows the size of echo reflected by the ultrasonic waves oscillated from the ultrasonic transducer 21 at the contact interface 3 between the objects to be joined 1 and one end face of the object 1 to be joined. It is schematically shown according to the joining progress state of the contact interface 3.
In (1) to (4) of FIG. 2, the size of the eco becomes smaller as the joining of the contact interface 3 progresses, and in (4), the joining of the contact interface 3 is completed and the eco from this side is completed. −
Indicates that has disappeared.

FIG. 3 shows a state in which the waveform of the echo reflected by the contact interface 3 and the end face of the article 1 to be bonded in each of (1) to (4) of FIG. 2 is observed by the above-mentioned oscilloscope 23. It is a thing. As shown in FIG. 3, as the joining progresses from (1) to (4), the size of the echo at the contact interface 3 becomes smaller, while the size of the eco at the one end face of the joined body 1 becomes smaller. It has been shown to grow.

FIG. 4 is a block diagram showing the overall construction of the joining apparatus of the second embodiment. In the joining apparatus of the second embodiment, the ultrasonic transducers 21A and 21B are attached to the respective end surfaces of the objects to be joined 1 and 2 and the ultrasonic transducer 21
While oscillating the ultrasonic pulse from A, the ultrasonic transducer 21
By receiving the ultrasonic pulse at B, the bonding state of the contact interface 3 between the objects to be bonded 1 and 2 is observed.

The ultrasonic transducers 21A and 21B are electrically connected to the ultrasonic flaw detector 22. The ultrasonic flaw detector 22 causes the ultrasonic transducer 21A to generate electric waves for ultrasonic pulse oscillation. While outputting the signal, ultrasonic transducer 2
A reception signal corresponding to the size of the ultrasonic pulse received in 1B is input from the ultrasonic transducer 21B. The ultrasonic flaw detector 22 displays the received waveform on the oscilloscope 23 based on the received signal output from the ultrasonic transducer 21B.

The controller 24, the microwave generator 15, the cavity 4, which are connected to the ultrasonic flaw detector 22,
The holding parts 5, 6 and the like are configured similarly to the first embodiment.

FIG. 5 shows that an ultrasonic pulse oscillated from the ultrasonic transducer 21A is received by the ultrasonic transducer 21B according to the bonding state of the contact interface 3 between the objects to be bonded 1 and 2. It schematically shows that the size of the changes. As shown in FIG. 5, as the joining progresses from (1) to (4), the echo (attenuation) at the contact interface 3 becomes smaller, and the magnitude of the ultrasonic pulse received by the ultrasonic transducer 21B becomes smaller. It shows that it grows.

FIG. 6 is a waveform diagram of the ultrasonic pulse reflected at the contact interface 3 in (1) to (4) of FIG. 5, respectively. As shown in (1) to (4) of FIG. It is shown that the echo (attenuation) at the contact interface 3 becomes smaller as it advances. Then, in (4), since the joining at the contact interface 3 is completed, the attenuation of the ultrasonic pulse at the contact interface 3 is almost zero.

FIG. 7 is a block diagram showing the overall construction of the joining apparatus of the third embodiment. In the joining apparatus of the third embodiment, when the ultrasonic transducer 21 is directly attached to the end surface of the article 2 to be joined in the joining apparatus of the first embodiment, the ultrasonic transducer 21 is thermally affected, so Does not exert its function sufficiently or may be damaged, one end surface of the water-cooling type ultrasonic introduction rod (ultrasonic transmission member) 31 is attached to the end surface of the article 2 to be bonded, By attaching the ultrasonic transducer 21 to the other end surface of the introducing rod 31,
It is configured to observe the bonding state of the contact interface 3 between the objects to be bonded 1, 2.

Therefore, the joining apparatus of the third embodiment is constructed by adding only the water-cooling type ultrasonic introducing rod 31 to the joining apparatus of the first embodiment. The ultrasonic wave introducing rod 31 is made of a material, for example, ceramics, which has substantially the same elastic characteristics as those of the objects to be joined 1 and 2. Further, since one end surface of the ultrasonic wave introducing rod 31 and the end surface of the joined body 2 are brought into contact with each other, a ceramic paste having elastic characteristics similar to those of the ultrasonic wave introducing rod 31 is used as an adhesive. Therefore, the ultrasonic transducer 2
No change in the transmission characteristics of the ultrasonic pulse oscillated from the ultrasonic pulse is generated by this ultrasonic pulse.
1, the object to be bonded 2, and the object to be bonded 1 are transmitted.

FIG. 8 shows that an ultrasonic pulse oscillated from the ultrasonic transducer 21 is bonded to the object 2 to be bonded, the contact interface 3 between the objects 1 and 2 and the object to be bonded via the ultrasonic wave introducing rod 31. 1
To the end surface of the object to be joined 1, the contact interfaces 3 of the objects to be joined 1 and the end surface of the object to be joined 2, and the size of each echo is determined according to the joining progress state of the contact interface 3. Is shown schematically. (1) to (4) of FIG.
As the joining of the contact interface 3 progresses, the size of the eco at the contact interface 3 becomes smaller, and in (4), it is shown that the joining of the contact interface 3 is completed and the eco from this surface disappears. There is.

FIG. 9 shows a state in which the waveform of the echo reflected on the contact interface 3 and the end faces of the objects to be joined 1 and 2 in FIGS. 8 (1) to 8 (4) is observed by the above-mentioned oscilloscope 23. Is shown. FIG. 9 shows (1) to (4)
As the joining progresses, the eco at the contact interface 3
Is smaller, the eco-value on the end faces of the objects to be joined 1 and 2 is larger.

FIG. 10 is a block diagram showing the overall construction of the joining apparatus of the fourth embodiment. The joining apparatus of the fourth embodiment is similar to the joining apparatus of the above-described second embodiment in that the ultrasonic transducers 21A and 2A are attached to the respective end faces of the objects to be joined 1 and 2.
Instead of directly attaching 1B, the ultrasonic transducers 21A, 2A are connected via water cooling type ultrasonic introducing rods 31A, 31B.
It is configured to wear 1B. Therefore, in this embodiment, the ultrasonic transducers 21A,
If the ultrasonic wave vibrators 21A and 21B do not sufficiently perform their functions or may be damaged due to thermal influences when they are directly attached.

As shown in FIG. 10, the bonding apparatus of the fourth embodiment oscillates ultrasonic pulses from the ultrasonic transducer 21A, and the ultrasonic wave introducing rod 31A, the object to be bonded 1, the contact interface 3, and the object to be bonded. It is configured to observe the bonding state of the contact interfaces 3 of the bonded bodies 1 and 2 by transmitting the bonded body 2 and the ultrasonic wave introducing rod 31B and receiving the ultrasonic pulse by the ultrasonic vibrator 21B. It is a thing.

The ultrasonic transducers 21A and 21B are electrically connected to the ultrasonic flaw detector 22. The ultrasonic flaw detector 22 causes the ultrasonic transducer 21A to generate electric waves for ultrasonic pulse oscillation. While outputting the signal, ultrasonic transducer 2
The reception signal corresponding to the size of the ultrasonic pulse received in 1B is input from the ultrasonic transducer 21B. The ultrasonic flaw detector 22 displays the received waveform on the oscilloscope 23 based on the received signal output from the ultrasonic transducer 21B.

FIG. 11 shows that an ultrasonic pulse oscillated from the ultrasonic transducer 21A is received by the ultrasonic transducer 21B according to the bonding state of the contact interface 3 between the objects to be bonded 1 and 2. It schematically shows that the size of the changes. As shown in FIG. 11, as the joining progresses from (1) to (4), the echo (attenuation) at the contact interface 3 becomes smaller and the magnitude of the ultrasonic pulse received by the ultrasonic transducer 21B becomes smaller. It shows that it grows.

FIG. 12 is a waveform diagram of the reflected wave of the ultrasonic pulse at the contact interface 3 in each of (1) to (4) of FIG. 11, and the joining progresses from (1) to (4) of FIG. It is shown that the reflected wave at the contact interface 3 becomes smaller as Then, in (4), since the joining at the contact interface 3 is completed, the reflected wave at the contact interface 3 becomes almost zero.

As described above, in each of the embodiments, the echo of the ultrasonic pulse at the contact interface 3 becomes gradually smaller during the process of heating and bonding the contact interface 3 of the objects to be joined 1 and 2 by the microwave. When the joining is completed, the echo of the ultrasonic pulse at the contact interface 3 becomes almost zero. Therefore, by observing that the echo of the ultrasonic pulse at the contact interface 3 has become almost zero, the progress and completion of bonding can be observed in real time. And
At this point, the output of the microwave generator 15 is suddenly reduced to prevent excessive melting at the contact interface 3.

In the above embodiments, the joining apparatus utilizing heating by microwaves has been described, but not limited to microwaves, it is possible to join by uniformly heating the contact interface of the objects to be joined. Devices are within the scope of the invention.

[0035]

As described above, according to the bonding apparatus of each of the first to fourth aspects, the ultrasonic pulse is introduced into the object to be bonded in the process of heating and bonding the contact interface of the object to be bonded. By observing the waveform of the ultrasonic pulse reflected at the contact interface of the object to be bonded or the transmitted waveform of the ultrasonic pulse, the bonding state at the contact interface can be directly recognized, so that reliable and high quality This has the effect of enabling joining. It is also possible to detect cracks in the article to be joined that occur as the article to be joined is heated.

[Brief description of drawings]

FIG. 1 is a block diagram showing an overall configuration of a first embodiment.

FIG. 2 is a schematic diagram showing stepwise the echo intensity of an ultrasonic pulse at a contact interface and an end face of an object to be joined.

FIG. 3 is a waveform diagram of echo of the ultrasonic pulse of FIG.

FIG. 4 is a block diagram showing an overall configuration of a second embodiment.

FIG. 5 is a schematic diagram showing the intensity of echo of an ultrasonic pulse at the contact interface of the objects to be joined in stages.

6 is a waveform diagram of the echo of the ultrasonic pulse of FIG.

FIG. 7 is a block diagram showing an overall configuration of a third embodiment.

FIG. 8 is a schematic diagram showing stepwise the echo intensity of an ultrasonic pulse at a contact interface and an end face of a body to be joined.

FIG. 9 is a waveform diagram of echo of the ultrasonic pulse of FIG.

FIG. 10 is a block diagram showing an overall configuration of a fourth embodiment.

FIG. 11 is a schematic diagram showing stepwise the intensity of echo of an ultrasonic pulse at the contact interface of the objects to be joined.

12 is a waveform diagram of echo of the ultrasonic pulse of FIG.

[Explanation of symbols]

 1, 2 Objects to be bonded 3 Contact interface 4 Cavity 5, 6 Holding part 15 Microwave generator 21 Ultrasonic transducer 21A, 21B Ultrasonic transducer 22 Ultrasonic flaw detector 23 Oscilloscope 24 Controller 31 Ultrasonic introduction Rod 31A Ultrasonic wave introducing rod 31B Ultrasonic wave introducing rod

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Masayasu Makihara Inventor Masayasu Makihara 1-20-20 Kitakousan, Otaka-cho, Midori-ku, Nagoya City Chubu Electric Power Co., Inc. Electric Power Research Laboratory (72) Inoue Seio Rokuno, Atsuta-ku, Nagoya 2-4-1, Incorporated Fine Ceramics Center (72) Inventor Yutaka Higashida 2-4-1, Rokuno, Atsuta-ku, Nagoya-shi Incorporated Fine Ceramics Center (72) Inventor Tsutomu Kadooka Atsuta, Nagoya 2-4-1, Rokuno-ku, Fine Ceramics Center Foundation (72) Inventor, Gotoshi Tobita 2-4-1-1, Rokuno, Atsuta-ku, Nagoya City Fine Ceramics Center

Claims (5)

[Claims] 1. A bonding apparatus for heating and bonding a contact interface of an object to be bonded, the ultrasonic vibrator being attached to one end surface of the object to be bonded, and an ultrasonic pulse from the ultrasonic vibrator. An ultrasonic pulse generator that emits the ultrasonic pulse to the object to be joined and an ultrasonic pulse that is incident on the object to be joined forms an echo waveform reflected at the contact interface of the object to be joined. A bonding apparatus comprising: an observation unit for observing a bonding state of the contact interface and occurrence of cracks in the bonded object by analysis. 2. An ultrasonic transducer, comprising: an ultrasonic transducer, which is attached to both end surfaces of a body to be joined with the contact interface of the body to be joined by heating, in a joining device. An ultrasonic pulse generator that emits an ultrasonic pulse from one of the ultrasonic transducers to cause the ultrasonic pulse to enter the object to be joined, and the ultrasonic pulse incident to the object to be joined is the ultrasonic pulse. An observation unit for observing the bonding state of the contact interface and the occurrence of cracks in the bonded body by analyzing the waveform of the ultrasonic pulse received by the ultrasonic vibrator on the side opposite to the ultrasonic vibrator that emitted the And a joining device. 3. A joining device for heating and joining a contact interface of an article to be joined, which is made of a material having elastic characteristics similar to those of the article to be joined, and one end face of which is an end surface of the article to be joined. The ultrasonic transmission member that guides the ultrasonic pulse to the object to be bonded in the state of being attached to the member and the elastic property similar to the elastic property of the ultrasonic transmission member, and one end surface of the ultrasonic transmission member. And an adhesive for adhering the end surface of the bonded body, an ultrasonic transducer adhered to the other end surface of the ultrasonic transmission member, and from the ultrasonic transducer via the ultrasonic transmission member An ultrasonic pulse generator that applies an ultrasonic pulse to the object to be joined, and an ultrasonic pulse that is applied to the object to be joined are analyzed by analyzing the waveform of echo reflected at the contact interface of the object to be joined. Bonding state of the contact interface and the bonded object And a observing section for observing the occurrence of cracks in the joining apparatus. 4. A joining device for heating and joining a contact interface of an article to be joined, wherein the joining object is formed of a material having elastic characteristics similar to those of the article to be joined, and one end face of each of the articles to be joined. And an elastic characteristic similar to the elastic characteristic of the first and second ultrasonic transmission members that pass the ultrasonic pulse in a state of being attached to the end surface of the first ultrasonic transmission member. An adhesive that attaches the end faces of the first and second ultrasonic transmission members to the end faces of the respective objects to be joined, and the adhesive that is attached to the end faces of the first and second ultrasonic transmission members. First and second ultrasonic transducers, and an ultrasonic pulse generator that causes an ultrasonic pulse to be incident from the first ultrasonic transducer on the object to be bonded via the first ultrasonic transmission member, The ultrasonic pulse incident on the bonded body is the second ultrasonic transmission unit. An observation unit for observing the bonding state of the contact interface and the occurrence of cracks in the bonded body by analyzing the waveform of the ultrasonic pulse received by the second ultrasonic transducer through the material. A joining device characterized by the above. 5. The joining apparatus according to claim 3, wherein the ultrasonic transmission member is made of ceramics and the adhesive is made of ceramic paste.