JP3340475B2 - Ultrasonic welding equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic transducer for generating ultrasonic waves from a plurality of ultrasonic vibrators, vibrating a welding jig, and welding an object to be welded in contact with a welding portion contact surface of the welding jig. The present invention relates to a sonic welding device.

[0002]

2. Description of the Related Art FIG. 4 shows a conventional ultrasonic welding apparatus which generates ultrasonic waves from a plurality of ultrasonic vibrators, vibrates a welding jig, and welds an object to be welded in contact with the welding jig. There is such a configuration. As shown in FIG. 4, this conventional ultrasonic welding apparatus is used to weld, for example, polyolefin-based polymer materials A1, A2 to be welded.
1. While the welding jigs B1, B2, B3, B4, and B5 are brought into contact with the welding jigs 1, the ultrasonic horns C1, C2, C3, C4, and C5 are brought into contact with the surface opposite to the welding jig. When ultrasonic waves are emitted from the ultrasonic vibrators D1, D2, D3, D4, and D5 to the ultrasonic horns C1, C2, C3, C4, and C5, the respective ultrasonic waves become ultrasonic horns. Vibration of the welding jigs B1, B2, B3, B4, and B5 where the tips of the components C1, C2, C3, C4, and C5 are in contact with each other to generate frictional heat between the workpieces A1 and A2 to weld them. It is to let.

[0003]

In the case of the above conventional ultrasonic welding apparatus, vibration energy is applied to the range of the welding objects A1 and A2 with which the welding jigs B1, B2, B3, B4 and B5 are in contact. In order to transmit the light uniformly, the ultrasonic horn C1,
C2, C3, C4, and C5 must have appropriate shapes and high processing accuracy. Therefore, the cost of the ultrasonic horns C1, C2, C3, C4, and C5 is increased, and the welding object A between the adjacent welding jigs is increased.
Since it is difficult for the energy of vibration to be transmitted to the portions 1 and A2, uniform welding is difficult, and there is a problem that poor welding may occur.

Accordingly, in the present invention, by controlling the phases of ultrasonic waves generated from a plurality of ultrasonic vibrators, an arbitrary range of an object to be welded can be uniformly welded by an integrated welding jig. An object of the present invention is to achieve high-quality welding without using a high-cost ultrasonic horn.

[0005]

The technical means for solving the above problem is that a plurality of ultrasonic vibrators are provided on the surface of the welding jig which is brought into contact with the welding portion of the object to be welded, on the surface opposite to the welding portion contact surface. The ultrasonic welding device for generating ultrasonic waves from the respective ultrasonic vibrators to vibrate the welding jig and weld the object to be welded is provided at one point of a welding part contact surface of the welding jig. Is provided with a phase control circuit that controls the phase of the ultrasonic waves generated from each of the ultrasonic transducers so that the maximum vibration point is scanned along the welding portion contact surface so that the maximum vibration point is scanned. It is to make a configuration.

[0006]

According to the ultrasonic welding apparatus having the above-described structure, the phase control circuit determines that one point of the welding portion contact surface of the welding jig is the maximum vibration point and that the maximum vibration point is at the welding portion contact surface. In order to control the phase of the ultrasonic waves generated from each of the ultrasonic transducers so as to scan along the same, the welding portion of the object to be welded is uniformly welded by scanning the maximum vibration point.

[0007]

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a conceptual diagram for welding objects A1 and A2 to be welded made of, for example, a polyolefin polymer material by ultrasonic waves. As shown in FIG.
The lower surface (welding site contact surface) of the integrated welding jig 1 is in contact with the welding portion 2. On the other hand, ultrasonic vibrators 2, 3, 4, 5, and 6 are arranged on the upper surface of the welding jig 1. In such a configuration, when an ultrasonic circuit having a waveform represented by each curve is generated from the ultrasonic vibrators 2, 3, 4, 5, and 6 by an electric circuit described later, each ultrasonic wave becomes a vibration wave. At the point where the vibration wave propagates through the welding jig 1 and has the same phase, that is, the amplitude of the vibration wave at the focal point F in the drawing is the sum of the amplitudes of the respective vibration waves, and the vibration energy at the focal point F becomes maximum. .

Next, the movement of the focal point F will be described with reference to FIG. In FIG. 2, the curve shown in the welding jig 1 simplifies the state of propagation of the ultrasonic waves generated from the ultrasonic transducers 2, 3, 4, 5, and 6,
A straight line shown by a solid line from each ultrasonic transducer 2, 3, 4, 5, 6 toward the focal point F1 is a corresponding one of the ultrasonic transducers 2, 3, 4, 4.
It represents the distance between 5, 6 and the focus F1. Focus F1 to focus F2
, The focal length from each of the ultrasonic transducers 2, 3, 4, 5, and 6 changes as shown by the dotted line. If a sound wave is generated, that is, the ultrasonic vibrator 2,
If the ultrasonic waves are generated with a time delay in the order of 3, 4, 6, and 5, it is possible to continuously move the focal point, and the same vibration energy is obtained at any moving point.

As described above, each of the ultrasonic transducers 2, 3,
If ultrasonic waves are generated with a time delay from 4, 5 and 6, the focal point F can be moved continuously, so that the welded portions of the objects A1 and A2 to be welded are continuously and uniformly welded. be able to.

Next, a control circuit according to an embodiment will be described with reference to FIG. As shown in FIG. 3, output circuits 7, 8, 9, 1, 1 are provided to the respective ultrasonic transducers 2, 3, 4, 5, and 6.
0 and 11 are connected. The output circuits 7, 8, 9,
Reference numerals 10 and 11 denote high-frequency currents for generating ultrasonic waves having a predetermined frequency from the respective ultrasonic transducers 2, 3, 4, 5, and 6 to the respective ultrasonic transducers 2, 3, 4, 5, and 6. I do. On the other hand, an oscillation circuit 1 for oscillating a high-frequency electric signal corresponding to the ultrasonic wave generated from each of the ultrasonic transducers 2, 3, 4, 5, 6
2 are provided. Then, the output circuits 7, 8,.
9, 10, 11 and the oscillation circuit 12
14, 15, 16 and 17 are connected. The delay circuits 13, 14, 15, 16 and 17 have a control circuit 1
8 are connected.

The control circuit 18 controls each of the ultrasonic transducers 2,
Ultrasonic waves are generated with a time delay in order from 3, 4, 5, and 6, and the focal point F is continuously moved so that the objects to be welded A1,
This is for controlling the continuous welding of the welding portion of A2.
That is, the control circuit 18 generates the ultrasonic waves generated from the respective ultrasonic transducers 2, 3, 4, 5, and 6 with respect to the delay circuits 13, 14, 15, 16, and 17 to move the focal point F. When this generation order command is given, the delay circuits 13, 14, 15, 16, 17 sequentially delay the output circuits 7, 8, 9, 10, 11 by a predetermined time. To transmit the high-frequency electric signal from the oscillation circuit 12. As a result, each of the output circuits 7, 8, 9, 10, 11
Is based on the input of the high-frequency electric signal,
A high-frequency current is applied to 3, 4, 5, 6 to generate ultrasonic waves from the respective ultrasonic transducers 2, 3, 4, 5, and 6. The delay time in the delay circuits 13, 14, 15, 16, 17 can be adjusted by each delay circuit or the control circuit 18.

As described above, the control circuit 18 generates ultrasonic waves from the ultrasonic vibrators 2, 3, 4, 5, and 6 in order with a time delay, continuously moves the focal point F, and welds the ultrasonic waves. Control is performed to continuously weld the welding portions of the objects A1 and A2.
This is, in other words, each ultrasonic transducer 2, 3,
By controlling the phase of the ultrasonic waves generated from 4, 5, and 6, the focal point F of the ultrasonic waves is scanned over the entire welded portions of the workpieces A1 and A2, and the welded portions of the workpieces A1 and A2 are continuously connected. In addition, they are uniformly welded. Therefore, the delay circuits 13, 14, 15, 16, 17 and the control circuit 18
This constitutes a phase control circuit described in the claims.

[0013]

As described above, according to the present invention, a plurality of ultrasonic vibrators are provided on a surface of a welding jig which comes into contact with a welding site of a workpiece to be welded, the surface being opposed to the welding site contact surface. In the ultrasonic welding apparatus that generates ultrasonic waves from the respective ultrasonic vibrators to vibrate the welding jig and weld the object to be welded, one point of a welding portion contact surface of the welding jig is a maximum vibration point. As such, and provided a phase control circuit for controlling the phase of the ultrasonic waves generated from each of the ultrasonic transducers so that the maximum vibration point is scanned along the welding portion contact surface,
It is possible to continuously and uniformly weld a welding portion of an object to be welded without using an expensive ultrasonic horn with high processing accuracy, which is always necessary in a conventional ultrasonic welding apparatus.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram of a configuration and a basic operation of an embodiment of the present invention.

FIG. 2 is a conceptual diagram illustrating a movement of a maximum vibration point of an ultrasonic wave according to an embodiment of the present invention.

FIG. 3 is a control block diagram of one embodiment of the present invention.

FIG. 4 is a configuration explanatory view showing a configuration of a conventional ultrasonic welding device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Welding jig 2-6 Ultrasonic vibrator 7-11 Output circuit 12 Oscillation circuit 13-17 Delay circuit 18 Control circuit A1, A2 Welding object

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B29C 65/08 B23K 20/10

Claims (1)

(57) [Claims] A plurality of ultrasonic vibrators are provided on a surface of a welding jig that is in contact with a welding site of a workpiece to be welded, the surface being opposed to a welding site contact surface, and ultrasonic waves are transmitted from each ultrasonic oscillator. An ultrasonic welding apparatus for generating and vibrating the welding jig to weld the object to be welded, wherein one point of a welding portion contact surface of the welding jig is a maximum vibration point, and the maximum An ultrasonic welding apparatus, comprising: a phase control circuit for controlling a phase of an ultrasonic wave generated from each of the ultrasonic vibrators so that a vibration point is scanned along a welding portion contact surface.