JP2002144434A - Apparatus and method for ultrasonic welding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an apparatus and a method for ultrasonic welding capable of always assuring a stable weld-penetration depth. SOLUTION: The apparatus for ultrasonic welding comprises a welding head (2) vertically moving by a cam (1) for realizing a periodical motion, an air cylinder (3) for giving a pressurizing force necessary for welding, a horn (4) disposed at a distal end of the head (2), and a spring (5) for raising the head (2). The method for ultrasonic welding comprises the steps of starting a vibration at the horn (4) when arriving at a preset pressurizing force after the horn (4) comes into contact with a work (6) to be welded, stopping the vibration at the horn (4) when arrived at the preset weld-penetration depth, and raising the head (2) by the cylinder (3) and the spring (5) after arriving at the preset final penetration depth or after completing preset cooling time retaining.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic welding apparatus and an ultrasonic welding method, and more particularly, to an ultrasonic welding apparatus for welding a workpiece such as an outer case of an electronic component made of a resin material using ultrasonic energy. The present invention relates to an ultrasonic welding device and an ultrasonic welding method.

[0002]

2. Description of the Related Art Conventionally, as an ultrasonic welding apparatus of this type, for example, the one shown in FIG. 7 has been known. Specifically, a cam (1) for realizing a periodic motion, a welding head (2) moved up and down by the cam (1), and a pressurizing spring (15) for applying a pressing force necessary for welding, And a horn (4) at the tip of the welding head (2). An ultrasonic welding method using such an ultrasonic welding device includes a welding head (2) using a cam (1). ) Is raised and lowered, and a pressing force required for welding is applied by a pressing spring (15).

[0003]

However, in such an ultrasonic welding apparatus and an ultrasonic welding method,
As shown in FIG. 8, the lower limit of the cam (1) is the welding head (2) at the position of the mountain side (11).
Because the welding head (2) is moved up and down by the cam (1),
The time at the lower limit was constant in the welding head (2).

Therefore, in the welding head (2), since the welding time + the cooling time is always constant, it is impossible to control the welding by the penetration depth. For this reason, when the welding time became unstable, the penetration depth varied.

The present invention has been made in view of the above-mentioned facts, and has as its object to provide an ultrasonic welding apparatus and an ultrasonic welding method which can always secure a stable penetration depth. Is to do.

[0006]

An ultrasonic welding apparatus according to a first aspect of the present invention comprises a welding head (2) which moves up and down by a cam (1) for realizing a periodic movement, and a welding head required for welding. An air cylinder (3) for applying pressure, a horn (4) at the tip of the welding head (2), and a spring (5) for raising the welding head (2) are provided.
Further, after the horn (4) comes into contact with the workpiece (6) to be welded and reaches a preset pressing force, the horn (4)
When the horn (4) starts vibrating and reaches a preset penetration depth, the horn (4) stops the vibration, and after reaching the preset final penetration depth or after completing the pressing of the preset cooling time, the air cylinder (3) The welding head (2) is raised by the spring (5).

In the ultrasonic welding method according to a second aspect of the present invention, the welding head (2) is moved up and down by a cam (1) for realizing a periodic movement, and the pressure required for welding is adjusted by an air cylinder (1). After the horn (4) at the tip of the welding head (2) comes into contact with the workpiece (6) to be welded, the horn (4) vibrates when it reaches a preset pressure. When the horn (4) reaches the preset penetration depth, the horn (4) stops the vibration, and after reaching the preset final penetration depth or after the pressing of the preset cooling time is completed, the air cylinder (3) )
And the welding head (2) is raised by a spring (5) above the air cylinder (3).

According to a third aspect of the present invention, there is provided an ultrasonic welding method, wherein after the preset final penetration depth is reached or after a preset cooling time is pressed, the welding head (2) is moved by the air cylinder (3). ) Until you lift
The self-weight of the welding head (2) is supported by the spring (5) so that no pressing force is applied.

According to the ultrasonic welding method of the present invention, when the welding head (2) is moving down at a high speed,
By switching the curve of the cam (1) immediately before the horn (4) comes into contact with the work (6), the welding head (2) is switched so as to descend at a low speed.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the drawings according to embodiments.

FIG. 1 is a perspective view schematically showing an ultrasonic welding apparatus according to one embodiment of the present invention. FIG. 2 is a schematic view showing an operation process of the ultrasonic welding device and the ultrasonic welding method according to one embodiment of the present invention. 3A to 3D are switch handles manufactured using the ultrasonic welding apparatus and the ultrasonic welding method of the present invention, and FIG. FIG. 4B is a plan view from the back of the handle, and FIG. 4B is a plan view from the surface of the switch handle for the triple type.
FIG. 4 is a plan view of the double-sided switch handle as viewed from the surface thereof, and FIG. 4D is a plan view of the single-sided switch handle viewed from the surface thereof. FIG. 4 is a cross-sectional view for explaining a problem in manufacturing the switch handle of FIG. FIGS. 5A and 5B are cross-sectional views for explaining a state when the switch handle of FIG. 3 is manufactured. FIG. 6 is a time chart in which the operation of the ultrasonic welding apparatus and the ultrasonic welding method according to one embodiment of the present invention is graphed.

As shown in FIGS. 1 to 6, an ultrasonic welding apparatus according to the present invention comprises a welding head (2) which moves up and down by a cam (1) for realizing a periodic movement, and a pressing force required for welding. An air cylinder (3) to be provided, a horn (4) at the tip of the welding head (2), and a spring (5) for raising the welding head (2).
Further, after the horn (4) comes into contact with the workpiece (6) to be welded and reaches a preset pressing force, the horn (4)
When the horn (4) starts vibrating and reaches a preset penetration depth, the horn (4) stops the vibration, and after reaching the preset final penetration depth or after completing the pressing of the preset cooling time, the air cylinder The welding head (2) is raised by (3) and the spring (5).

The cam (1) is for realizing a periodic movement. Specifically, this cam (1) is a contact transmission mechanism for realizing various periodic movements.
The cam (1) is adapted to be rotated by a driving body (9) as shown in FIG. In the present embodiment, the cam (1) has a circular shape as shown in [1] of FIGS. 1 and 2, but may have another shape as necessary. You can do it.

The welding head (2) is shown in FIG.
As shown in [5], it is moved up and down by the cam (1). A horn (4) is provided at the tip of the welding head (2) as shown in FIGS.
The horn (4) concentrates ultrasonic energy generated from an ultrasonic generating unit or the like.

The air cylinder (3) provides a pressing force necessary for welding. At the tip of the air cylinder (3), for example, a load cell (8) is provided as shown in FIGS. A piston or the like may be provided in the air cylinder (3) as necessary.

The spring (5) is for raising the welding head (2). The material and shape of the spring (5) are not particularly limited as long as the spring (5) can raise the welding head (2). In this embodiment, the spring (5) is provided above the air cylinder (3) as shown in FIGS. 1 and 2, but is not limited to this. Things.

The work (6) is to be welded, is sandwiched by the horn (4) together with the receiver (19), and is pressed. Then, when pressed, the work (6) is contained in the pallet (20). The work (6) is, for example, a switch handle (7) as shown in FIGS.

In the case of such a switch handle (7), a triple handle may be formed as shown in FIGS. 3 (a) and 3 (b) or (c) of FIG. ) May be formed as shown in FIG. 3 (d), or a single-dial type may be formed as shown in FIG. 3 (d).

In the case of such a switch handle (7), the welding surface (10) is substantially at the center in this embodiment as shown in FIG. 3A, but is not limited to this. Is not. By the way, FIG.
A cross section taken along the line AA ′ of FIG. 4 is shown in [1] and [2] of FIG. 4 except for the horn (4) and the receiver (19).

As described above, when the switch handle (7) is manufactured, as shown in [1] and [2] of FIG. 4, the switch is pressed by the horn (4) and the receiver (19) as indicated by an arrow. When the welding margin (18) provided between the first part (16) and the second part (17) and serving as an energy director is greatly collapsed, a switch handle (7) such as In some cases, the melting point of the molded product may be different from the bonding surface. However, as shown in FIG. 5A, when the surface area of the contact surface of the welding margin (18) is minimized, the horn (4 ) And pressed by the receiver (19),
As shown in FIG. 5 (b), the welding surface (18) collapses as shown in FIG. 5 (b), and the surface area of the contact surface becomes large, and thereafter it becomes difficult to melt, which is preferable. By the way, if the welding margin (18) is crushed, no heat is generated at the contact surfaces between the parts to be welded, so that the welding strength becomes unstable, which is inconvenient.

In the present invention, [1] to [2] in FIG.
After the horn (4) comes into contact with the work (6) as shown in (1), when the load cell (8) provided in the embodiment reaches a preset pressing force, the horn (4)
Starts vibrating, and the horn (4) stops vibrating when it reaches a preset penetration depth as shown in [3] of FIG.

Then, as shown in [4] to [5] in FIG. 2, after reaching the preset final penetration depth or after completing the pressing of the preset cooling time, the air cylinder (3)
And the welding head (2) is raised by the spring (5).

According to the present invention, an air cylinder (3) for applying a pressure required for welding, while being driven by a cam (1) for realizing a periodic motion, and an air cylinder (3) having such a structure. With the spring (5) at the upper part of the cylinder (3), the welding head (2) is raised to secure the penetration accuracy, and
Since the cooling time can be controlled by the air cylinder (3) itself, a stable penetration depth can be secured.
In addition, the mechanism of the cam (1) can be used for high-speed equipment because the feed mechanism and the motivation can be removed, which is very useful.

That is, the present invention can always ensure a stable penetration depth.

Further, in the ultrasonic welding method of the present invention, as shown in FIGS. 1 to 6, the welding head (2) is moved up and down by a cam (1) for realizing a periodic movement, and necessary for welding. The pressing force is applied by the air cylinder (3), and then, after the horn (4) at the tip of the welding head (2) comes into contact with the workpiece (6) to be welded, the pressing force reaches the preset pressing force. When the horn (4) starts to vibrate and reaches a preset penetration depth, the horn (4) stops vibrating, and after reaching a preset final penetration depth or after pressing a preset cooling time. The welding head (2) is raised by the air cylinder (3) and a spring (5) above the air cylinder (3).

According to the present invention, by employing such a manufacturing method, an air cylinder (3) for applying a pressing force necessary for welding, while being driven by a cam (1) for realizing a periodic movement, is provided. Since the spring (5) above the air cylinder (3) raises the welding head (2), the penetration accuracy can be ensured, and the cooling time can be controlled by the air cylinder (3) itself. In addition, a stable penetration depth can be secured. In addition, the mechanism of the cam (1) can be used for high-speed equipment because it can be motivated by the feed mechanism, which is very useful.

That is, the production method of the present invention can always ensure a stable penetration depth.

As shown in FIGS. 1 and 2, after reaching the preset final penetration depth or after completing the preset cooling time, the welding head (2) is lifted by the air cylinder (3). In the meantime, if the self-weight of the welding head (2) is supported by the spring (5) so that no pressing force is applied, the self-weight of the welding head (2) is supported by the spring (5). In particular, it can be more reliably prevented from further melting.

That is, in this case, the self-weight of the welding head (2) is supported by the spring (5) so that the self-weight of the welding head (2) is not applied during the valve switching time of the air cylinder (3). Things. In addition, as a valve of this air cylinder (3), usually,
A solenoid valve is employed.

Further, when the welding head (2) is descending at a high speed, the horn (4) is attached to the work (6).
If the welding head (2) is switched so as to descend at a low speed by switching the curve of the cam (1) immediately before the contact, the welding head (2) descends from a high speed to a low speed. And the welding head (2) is restrained from lowering in acceleration, and the horn (4) is more reliably pressed against the welding margin (18) due to the impact when the horn (4) comes into contact with the work (6). It can be reduced, so that the welding is very stable.

FIG. 6 is a time chart showing the operation of the ultrasonic welding apparatus and the ultrasonic welding method of the present invention in a graph. Such an ultrasonic welding apparatus and the ultrasonic welding method are summarized. Thereby, a stable penetration depth can always be ensured.

[0032]

According to the ultrasonic welding apparatus according to the first aspect of the present invention, the air cylinder (3) for applying the pressing force necessary for welding while being driven by the cam (1) for realizing the periodic movement. ) And the spring (5) above the air cylinder (3), the welding head (2) can be raised to secure the penetration accuracy, and the air cylinder (3) itself can reduce the cooling time. Because it can be controlled, a stable penetration depth can be secured. In addition, the mechanism of the cam (1) can be used for high-speed equipment because it can be motivated by the feed mechanism, which is very useful.

That is, the present invention can always ensure a stable penetration depth.

According to the ultrasonic welding method according to the second aspect of the present invention, the air cylinder (3) for applying the pressing force necessary for welding while being driven by the cam (1) for realizing the periodic movement. By using the spring (5) above the air cylinder (3), the welding head (2) can be raised to secure the penetration accuracy, and the cooling time can be controlled by the air cylinder (3) itself. Therefore, a stable penetration depth can be secured. In addition, the mechanism of the cam (1) can be used for high-speed equipment because it can be motivated by the feed mechanism, which is very useful.

That is, the manufacturing method of the present invention can always ensure a stable penetration depth.

According to the ultrasonic welding method according to the third aspect of the present invention, in addition to the case described in the second aspect, the spring (5) further supports the own weight of the welding head (2) and further melts. This can be more reliably prevented.

According to the ultrasonic welding method of claim 4 of the present invention, in addition to the case of claim 2 or claim 3,
The welding head (2) is switched so as to descend from a high speed to a low speed, the acceleration when the welding head (2) descends is suppressed, and the horn (4) is impacted when the horn (4) comes into contact with the work (6). The crushing of the welding margin (18) can be reduced more reliably, so that the welding is very stable.

[Brief description of the drawings]

FIG. 1 is a perspective view schematically showing an ultrasonic welding device according to an embodiment of the present invention.

FIG. 2 is a schematic view showing an operation process of the ultrasonic welding device and the ultrasonic welding method according to one embodiment of the present invention.

3 (a) to 3 (d) are switch handles manufactured using the ultrasonic welding apparatus and the ultrasonic welding method of the present invention, and FIG. 3 (a) is a switch for a triple type. (B) is a plan view of the switch handle for the triple type as viewed from the front side,
(C) is a plan view as seen from the surface of the double switch handle, and (d) is a plan view as seen from the surface of the single switch handle.

FIG. 4 is a cross-sectional view for explaining a problem in manufacturing the switch handle of FIG.

5 (a) and 5 (b) are cross-sectional views for explaining a state when the switch handle of FIG. 3 is manufactured.

FIG. 6 is a time chart showing the operation of the ultrasonic welding apparatus and the ultrasonic welding method according to an embodiment of the present invention in a graph.

FIG. 7 is a perspective view schematically showing an ultrasonic welding apparatus according to a conventional example.

FIG. 8 is a plan view showing a state of a cam used in an ultrasonic welding apparatus according to a conventional example, viewed from an arrow E in FIG. 7;

[Explanation of symbols]

 Reference Signs List 1 cam 2 welding head 3 air cylinder 4 horn 5 spring 6 work

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Masaya Hirata 1048 Kadoma Kadoma, Osaka Prefecture Matsushita Electric Works, Ltd. F term (reference) 4F211 AD04 AH42 AP02 AP11 AR02 AR12 TA01 TC14 TD11 TN22 TQ05 TQ10 TQ11

Claims (4)

[Claims] 1. A welding head that moves up and down by a cam for realizing a periodic motion, an air cylinder that applies a pressing force necessary for welding, and a horn at a tip of the welding head.
A spring for raising the welding head is provided,
Further, after the horn comes into contact with the workpiece to be welded, when the horn reaches a preset pressure, the horn starts to vibrate, and when the horn reaches a preset penetration depth, the horn stops the vibration and the preset horn stops. An ultrasonic welding apparatus characterized in that the welding head is raised by the air cylinder and the spring after reaching the final welding depth or after pressing down for a predetermined cooling time. 2. A welding head is moved up and down by a cam for realizing a periodic motion, a pressing force required for welding is applied by an air cylinder, and then a horn at the tip of the welding head is attached to a workpiece to be welded. After contacting, the horn starts vibrating when it reaches a preset pressure, and stops oscillating when it reaches a preset penetration depth, or after reaching a preset final penetration depth or An ultrasonic welding method, wherein after the pressing for a predetermined cooling time is completed, the welding head is raised by the air cylinder and a spring above the air cylinder. 3. The same welding is performed by the spring so that no pressing force is applied until the welding head is lifted by the air cylinder after the preset final penetration depth is reached or after the pressing of the preset cooling time is completed. 3. The ultrasonic welding method according to claim 2, wherein the weight of the head is supported. 4. When the welding head is descending at a high speed, the curve of the cam is switched just before the horn comes into contact with the workpiece, thereby switching the welding head to descend at a low speed. The ultrasonic welding method according to claim 2 or 3, wherein: