CN114393290A

CN114393290A - Ultrasonic welding mould and ultrasonic welding device

Info

Publication number: CN114393290A
Application number: CN202110447985.2A
Authority: CN
Inventors: 刘光辉; 陈利权; 曹锐; 何臣臣; 朱鹏翔
Original assignee: Hubei Eve Power Co Ltd
Current assignee: Hubei Eve Power Co Ltd
Priority date: 2021-04-25
Filing date: 2021-04-25
Publication date: 2022-04-26

Abstract

The invention discloses an ultrasonic welding die and an ultrasonic welding device, wherein the ultrasonic welding die comprises a welding head consisting of a plurality of welding teeth, and the shape of the welding head is trapezoidal. The welding print of the ultrasonic welding die is trapezoidal, when the welding area is large and two times of welding are needed, after the first welding is finished, the workpiece to be welded is rotated by 180 degrees to carry out the second welding, and equivalently, the two right-angle trapezoids are spliced together. Therefore, the distance between the welding marks of the two times of welding is at least one welding tooth, and compared with the two square welding marks in the prior art, the distance between the two welding marks is increased, so that the problem that the two welding marks are too close to cause the fracture of the workpiece to be welded or the falling of the fusion part is avoided. And an ultrasonic welding die with a large welding area is not needed, and the service life of the ultrasonic welding device is not influenced.

Description

Ultrasonic welding mould and ultrasonic welding device

Technical Field

The invention relates to the technical field of mold design, in particular to an ultrasonic welding mold and an ultrasonic welding device.

Background

At present, ultrasonic welding gains acceptance of various industries due to the unique advantages of high welding speed, high welding strength, short welding time, no need of any scaling powder, no spark during welding, environmental protection, safety and the like. Ultrasonic welding is performed by transmitting a high-frequency vibration wave to the surfaces of two objects to be welded, and rubbing the surfaces of the two objects against each other under pressure to form a fusion between the molecular layers.

In the conventional ultrasonic welding apparatus, a circular shape or a square shape is generally used as a welding pattern shape of an ultrasonic welding die, and as shown in fig. 1, an example in which the welding pattern shape is a square shape is shown. In fig. 1, a square solder mark is formed by combining a plurality of solder tooth arrangements.

When the surface area of an object to be welded is large, the welding requirement cannot be met by one-time welding, two times of welding are needed, or an ultrasonic welding die with a large welding mark area is used. The ultrasonic welding die with a large welding area needs an ultrasonic welding device to output more energy at one time. This has a high demand on the ultrasonic welding apparatus, and the ultrasonic welding apparatus is easily damaged when its load is high, which affects its service life. When two times of welding are carried out on the same workpiece to be welded, the welding distance of the two times of welding is too close, so that the workpiece to be welded is easy to break, and the appearance and the performance of the workpiece to be welded are influenced; due to high-frequency vibration, the fusion part of the finished first welding is easy to fall off during the second welding, and the welding strength is reduced. Generally, the number of welding times does not exceed two. Since the fewer the number of welds in a limited space, the better. Two times of welding are used, mainly because when the welding area is large, the power required by one time of welding is large, and the service life of the ultrasonic welding device is influenced.

Disclosure of Invention

The invention aims to provide an ultrasonic welding die and an ultrasonic welding device, which can solve the problem of high load caused by the use of an ultrasonic welding die with a large welding area when the welding surface area is large in the prior art. The problems of welding part fracture and fusion part falling caused by more than two times of welding can be solved.

The purpose of the invention is realized by the following technical scheme:

in a first aspect, the present application discloses an ultrasonic welding die, comprising a welding head composed of a plurality of welding teeth, wherein the welding head is trapezoidal in shape.

Further, the welding head is in the shape of a right trapezoid.

Further, when the welding head is used for welding twice, the bevel edge of the welding mark formed by the first welding is adjacent to the bevel edge of the welding mark formed by the second welding.

Further, the length difference between the upper bottom edge and the lower bottom edge of the welding head is the length of one welding tooth.

Further, the ultrasonic welding mould further comprises a connecting part, and the welding head is arranged on the connecting part.

In a second aspect, the application discloses an ultrasonic welding device, comprising the ultrasonic welding die.

Furthermore, the ultrasonic welding device also comprises an ultrasonic generator, an energy converter and an amplitude transformer, wherein the ultrasonic generator, the energy converter and the amplitude transformer are sequentially connected.

Further, the ultrasonic generator converts current into high-frequency electric energy, the transducer converts the high-frequency electric energy into mechanical motion with the same frequency as the high-frequency electric energy, and the amplitude transformer adjusts the amplitude of the mechanical motion and then transmits the mechanical motion to the welding head.

Further, the high-frequency electric energy is electric energy with the unit of KHz.

Furthermore, the ultrasonic welding device also comprises a lower die, and a workpiece to be welded is fixed on the lower die during ultrasonic welding.

The welding print of the ultrasonic welding die is trapezoidal, when the welding area is large and two times of welding are needed, after the first welding is finished, the workpiece to be welded is rotated by 180 degrees to carry out the second welding, and equivalently, the two right-angle trapezoids are spliced together. Therefore, the distance between the welding marks of the two times of welding is at least one welding tooth, and compared with the two square welding marks in the prior art, the distance between the two welding marks is increased, so that the problem that the two welding marks are too close to cause the fracture of the workpiece to be welded or the falling of the fusion part is avoided. And an ultrasonic welding die with a large welding area is not needed, and the service life of the ultrasonic welding device is not influenced.

Drawings

FIG. 1 is a schematic view of the shape of the horn of a prior art ultrasonic welding die;

FIG. 2 is a schematic view of a weld mark structure formed during secondary welding using a prior art ultrasonic welding die;

FIG. 3 is a schematic view of the horn of the right trapezoid ultrasonic welding die of the present invention;

FIG. 4 is a schematic view of the horn of the right trapezoid ultrasonic welding die of the present invention;

fig. 5 is a schematic view of a structure of a weld mark formed when secondary welding is performed using the ultrasonic welding die of the present invention.

Detailed Description

The embodiments of the present disclosure are described in detail below with reference to the accompanying drawings.

The embodiments of the present disclosure are described below with specific examples, and other advantages and effects of the present disclosure will be readily apparent to those skilled in the art from the disclosure in the specification. It is to be understood that the described embodiments are merely illustrative of some, and not restrictive, of the embodiments of the disclosure. The disclosure may be embodied or carried out in various other specific embodiments, and various modifications and changes may be made in the details within the description without departing from the spirit of the disclosure. It is to be noted that the features in the following embodiments and examples may be combined with each other without conflict. All other embodiments, which can be derived by a person skilled in the art from the embodiments disclosed herein without making any creative effort, shall fall within the protection scope of the present disclosure.

The ultrasonic welding mould comprises a welding head consisting of a plurality of welding teeth, wherein the shape of the welding head is trapezoidal. When the welding head is used for welding, a trapezoidal welding mark is formed. As shown in fig. 3, a plurality of teeth 11 are arranged and grouped together to form a weld head 1.

Further, the shape of the horn 1 is a right trapezoid. The right trapezoid can ensure the distance between welding marks formed by two times of welding to be increased under the condition of ensuring the maximum welding area. An isosceles trapezoid or generally trapezoidal horn would also achieve the objectives of the present application, but with relatively few teeth, the resulting weld footprint would be relatively small. As shown in fig. 4, which is an example of a bonding tool in the shape of an isosceles trapezoid, 1 welding tooth is omitted compared to the right-angled trapezoid of fig. 3, and the area of the weld mark formed during welding is correspondingly reduced.

The working principle and the beneficial effects are explained as follows:

ultrasonic welding is the conversion of 50/60 Hz current to 15, 20, 30 or 40 KHz electrical energy by an ultrasonic generator. The converted high-frequency electrical energy is converted again into mechanical motion of the same frequency by the transducer, and the mechanical motion is then transmitted to the welding head by a set of amplitude transformer devices which can change the amplitude. The welding head transmits the received vibration energy to a joint of the workpieces to be welded, and the vibration energy is converted into heat energy in a friction mode in an area where the welding head is in contact with the joint, so that the workpieces to be welded are melted, and a welding mark is formed.

The larger the welding area, the larger the energy that the ultrasonic generator needs to output in one welding. When the output energy is close to or exceeds the upper limit of the power of the ultrasonic generator, the ultrasonic generator is easy to damage. However, in order to secure the degree of firmness of welding, the welding area cannot be reduced. To ensure a sufficient welding area, two times of welding are generally adopted in the process. If an existing horn is used, the two welds may be too close in impression distance, as shown in fig. 2. In this case, the ultrasonic vibration at the time of the second welding easily causes the work to be welded to be cracked between the two welding marks, and even causes the fused portion of the first welding to fall off.

The welding head of the ultrasonic welding die is designed into a right trapezoid, after the first welding is completed, the workpiece to be welded is rotated by 180 degrees to be welded for the second welding, and the oblique sides of the two right trapezoid welding marks are adjacent to each other, as shown in fig. 4. The right angle trapezoidal configuration increases the distance between two solder impressions, with a spacing of at least 1 tooth between a and a 'and b' respectively. The problem of a rectangular structure is avoided while the welding area is ensured, and the welding quality is improved.

Furthermore, the length difference between the two bottom edges of the welding head of the right trapezoid is not easy to be overlarge, and the size of one welding tooth is controlled to ensure the welding area. If the length difference is too large, the welding area is correspondingly reduced, and the welding firmness is affected.

Further, the ultrasonic welding mould also comprises a connecting part, and the welding head is arranged on the connecting part. One end of the connecting part is connected with an amplitude transformer of the ultrasonic welding device, and the amplitude transformer provides high-frequency mechanical vibration.

The specific operation process is as follows:

1. the trapezoidal welding head is used for welding a workpiece to be welded for the first time to form a first right-angled trapezoidal welding mark;

2. horizontally moving the workpiece to be welded and rotating the workpiece to be welded at 180 ℃ for second welding to form a second right-angled trapezoid welding mark;

3. the hypotenuses of the two right trapezoid solder prints are adjacent, and the welding effect is shown in fig. 4.

The application also discloses an ultrasonic welding device, including above-mentioned ultrasonic welding mould.

Furthermore, the ultrasonic welding device also comprises an ultrasonic generator, an energy converter and an amplitude transformer, wherein the ultrasonic generator converts current into high-frequency electric energy, the energy converter converts the high-frequency electric energy into mechanical motion with the same frequency, and the amplitude transformer adjusts the amplitude of the mechanical motion and then transmits the mechanical motion to the welding head.

The high-frequency electric energy refers to electric energy with the unit of KHz.

Further, the ultrasonic welding device also comprises a lower die, and the lower die is used for placing and fixing the workpiece to be welded. During welding, a workpiece to be welded is arranged between the ultrasonic welding die and the lower die.

In the description of the present invention, it is to be understood that the terms "intermediate", "length", "upper", "lower", "front", "rear", "vertical", "horizontal", "inner", "outer", "radial", "circumferential", and the like, indicate orientations and positional relationships that are based on the orientations and positional relationships shown in the drawings, are used for convenience in describing the present invention and for simplicity in description, and do not indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and therefore, are not to be construed as limiting the present invention.

In the present invention, unless otherwise expressly stated or limited, the first feature may be "on" the second feature in direct contact with the second feature, or the first and second features may be in indirect contact via an intermediate. "plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; may be mechanically coupled, may be electrically coupled or may be in communication with each other; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

The above description is for the purpose of illustrating embodiments of the invention and is not intended to limit the invention, and it will be apparent to those skilled in the art that any modification, equivalent replacement, or improvement made without departing from the spirit and principle of the invention shall fall within the protection scope of the invention.

Claims

1. The ultrasonic welding die comprises a welding head consisting of a plurality of welding teeth, and is characterized in that the welding head is trapezoidal in shape.

2. The ultrasonic welding die of claim 1, wherein the horn is shaped as a right trapezoid.

3. An ultrasonic welding die according to claim 1 or 2 wherein, in two welds using the horn, the bevel of the weld formed by the first weld is adjacent to the bevel of the weld formed by the second weld.

4. The ultrasonic welding die of claim 2, wherein the difference in length between the upper and lower base edges of the horn is the length of one tooth.

5. The ultrasonic welding die of claim 1 or 2, further comprising a connecting portion on which the horn is disposed.

6. An ultrasonic welding apparatus comprising the ultrasonic welding die of any one of claims 1, 2, and 4.

7. The ultrasonic welding apparatus of claim 6 further comprising an ultrasonic generator, a transducer and a horn, said generator, transducer and horn being connected in series.

8. The ultrasonic welding apparatus of claim 7, wherein the ultrasonic generator converts the current into high frequency electrical energy, the transducer converts the high frequency electrical energy into a mechanical motion having the same frequency as the high frequency electrical energy, and the horn adjusts the amplitude of the mechanical motion and transmits the adjusted mechanical motion to the horn.

9. The ultrasonic welding device of claim 8, wherein the high frequency electrical energy is electrical energy in KHz.

10. The ultrasonic welding apparatus of claim 7 further comprising a lower die to which the work piece to be welded is secured.