KR101495118B1 - apparatus for supersonic welding and method of supersonic welding - Google Patents

Abstract

A transfer device connected to the ultrasonic welding part for transferring the ultrasonic welding part; a transfer device for detecting the direct contact with the object part of the welding object and storing the position at the time point as a reference position; The ultrasonic welding unit stops the operation of the ultrasonic welding unit when the ultrasonic welding unit moves at a predetermined distance from the stored reference position to thereby stop the operation of the ultrasonic welding unit, And a linear sensor for generating a retraction signal, and a fusing method using the ultrasonic fusing apparatus.
According to the present invention, even if the position of the contact point where the horn and the object part meet differs slightly each time the welding operation is performed due to the error in the position of the object part of the object to be fused, the degree of fusing is directly measured, The state can be made uniform and appropriate.

Description

[0001] The present invention relates to an ultrasonic welding apparatus and an ultrasonic welding method,

The present invention relates to an ultrasonic fusing apparatus and a fusing method using the same, and more particularly, to an ultrasonic fusing apparatus capable of securing an appropriate fusing state even when the position of a contact between a horn and an object at the time of fusing is not constant, .

Generally, ultrasonic welding is performed by converting an electric oscillation made through an oscillator from a ultrasonic transducer to a mechanical vibration, amplifying the vibration through a booster and a tool horn, then transferring the mechanical energy to the object to be bonded, Refers to a fusing method in which the frictional heat generated in the fusing step softens and melts the adhesive surface, thereby causing fusing.

Ultrasonic welding does not require any adhesive or solvent, and there is little deformation or damage on the surface of the fused material. The basic structure and action of an ultrasonic welding apparatus used for ultrasonic welding are well known.

FIGS. 1 and 2 are schematic diagrams showing a state in which welding is prepared and a state in which welding is performed in an example of a conventional ultrasonic welding apparatus.

An ultrasonic fused portion 20 for performing ultrasonic welding and a transfer device for moving the ultrasonic fused portion are provided. The ultrasonic fused portion 20 includes an ultrasonic transducer 23 connected to a power source or the like (not shown) and a horn (tool horn) 21 attached thereto. The ultrasonic fused portion 20 is fixedly connected to the transfer device through a connection portion.

The transfer device is constituted around the pneumatic cylinder 10. The transfer device is fixed to the cylinder loader 90 which can be exposed to the outside of the pneumatic cylinder by being connected to the piston by advancing and retreating the piston (not shown) The guide portion 50 is moved forward and backward.

Therefore, the ultrasonic welding portion joined to the connection portion also advances and retreats. The horn of the ultrasonic fused portion 20 also advances and retreats and hits or falls on the target portion of the work piece 100. [ A sensor for sensing the position of a critical portion such as a piston or a horn 21 in the pneumatic cylinder 10 and a rear sensor 60 and a front sensor 70 for sensing the position of the piston in the pneumatic cylinder 10, Respectively.

Accordingly, when the piston of the pneumatic cylinder 10 is operated and the horn 21 advances and the connecting portion reaches the calculated joint position so that the horn 10 touches the fused portion, the front sensor 70 senses the piston position Thereby generating an electric signal. In response to the signal from the front sensor 70, ultrasonic welding is performed in the ultrasonic welding unit 20, and an object to be welded is fused through the horn 21.

More specifically, in the ultrasonic oscillation, a timer (not shown) is reset and operated when a timer in the ultrasonic welding unit receives a signal from the front sensor 70, and ultrasonic oscillation is performed only within the operation period of the timer. When a predetermined time elapses in the timer, the timer stops operating and the ultrasonic oscillation is also stopped.

Further, the electric signal generated with the stop of the ultrasonic oscillation activates the valve of the pneumatic pressure applying line, which regulates the pneumatic pressure of the pneumatic cylinder 10 of the transfer device, so that the piston returns to the retreat point position which is the fusing work waiting position again. When the piston reaches the retreat point position, the rear sensor (60) senses this and generates an electric signal to stop the valve operation and stop the operation of the piston.

On the other hand, if the ultrasonic welding portion including the horn 21 moves forward without limitation, there is a problem in the fusion state of the fusion object 100 and a defect may occur, so that the fusion state of the fusion object is not affected at the forefront position And a stopper (80) for preventing the piston or the cylinder loader or a portion of the ultrasonic welded portion from contacting with the battery is provided at that position.

However, when the horn 21 comes into contact with the target portion of the object to be welded 100 and the piston or the connection portion comes to a predetermined position, the front sensor 70 does not sense the object, So that a signal is generated. Therefore, there is no guarantee that the point of time when the front sensor 70 sends a signal and the point of time when the ultrasonic horn exactly touches the welded portion exactly coincides with each other. In fact, the target portion of the object to be welded is not always in the correct position, The timer and the ultrasonic welder may start to operate before reaching the target object site. Since the timer operates only for a predetermined period of time, in this case, the actual welding time is shortened so that sufficient welding can not be performed, which may result in defective welding process.

On the other hand, if progress is stopped by touching the ultrasonic horn before the front sensor detects, the timer and the ultrasonic welding part may not operate and ultrasonic welding may not be performed until the equipment is set again.

The position of the fusion-bonded portion of the object to be fusion-bonded can be changed according to the season, the ambient temperature, the humidity change, the transient change depending on the time of the nearby mechanical equipment, etc. Therefore, It is very cumbersome and time-consuming to appropriately adjust the position of the detection position or the position of the object to be fused so that the process efficiency and the operating rate are lowered.

Published patent application No. 10-2012-0025831

SUMMARY OF THE INVENTION The present invention has been made to solve the problems of the above-described embodiments, and it is an object of the present invention to provide an apparatus and a method for adjusting the position of a contact point, Time heating is performed so that the fusion state in the object to be fusion can be uniformly and appropriately performed.

In order to achieve the above object, the ultrasonic fusing apparatus of the present invention comprises:

A transfer unit for transferring the ultrasonic welding unit; a transfer unit for directly sensing that the transfer unit is advanced to the object region of the object to be welded and storing the position at the time point; and the ultrasonic welding unit And a linear sensor for generating a retraction signal for stopping the operation of the ultrasonic welding unit and for retracting the transfer device by detecting the distance when the ultrasonic welding unit proceeds at a predetermined distance from the stored position, .

The present invention may further include a rear sensor for detecting a retreat position of the ultrasonic fused portion and stopping the retraction of the transfer device.

In the present invention, it is preferable to provide a controller unit for starting and stopping a signal of a sensor means such as a linear sensor, a feeding device operation, and an ultrasonic oscillation, for automation of operation, and the controller unit supplies power And adjusting the elements in a manner that stops them.

In the present invention, the ultrasonic welded part travels a certain distance. The ultrasonic welding is performed after the contact position where the object to be welded and the ultrasonic horn meet is sensed and the initial position is confirmed. The fusion object is melted at the initial contact position by the action of the ultrasonic horn, Which means that the melted material in the fusion region spreads to the periphery by the continuous pressure application, and the portion is finely thinned so that the horn advances a certain distance. At this time, when the linear sensor senses that a predetermined distance has progressed, a signal is generated to stop the ultrasonic oscillation and to continue the operation of retracting the ultrasonic horn.

In the present invention, the linear sensor may be a contact type linear sensor such as a linear variable differential transformer (LVDT). In this case, in the contact type linear sensor, one end of a probe in the form of a guide bar is held in contact with a fixed part in the device, and the remaining part of the linear sensor is fixed to the ultrasonic welding part, the cylinder loader, It is possible to detect and store a position at which the first horn contacts the object to be welded while moving along the probe, and to check whether the horn reaches a predetermined distance from the stored position to generate a signal.

According to the embodiment, the probe of the linear sensor may be resiliently inserted into the linear sensor body and may have a compression type in which the length thereof is reduced when seen from the outside, and the probe may penetrate the remaining part, and when the probe is shortened from the front, The protruding length of the probe may become longer. At this time, when the linear sensor moves in a direction in which the length of the probe protruding forward from the main body (the remaining part of the probe) is moved, elastic energy is accumulated by the elastic body coupled with the probe, and when the linear sensor moves in the reverse direction, The length of the probe can be made long.

A contact type linear sensor such as an LVDT that can be used in the present invention sends a signal of a sensor value according to the movement distance and detects the movement of the sensor by a program built in the arithmetic unit so that the actual ultrasonic welding unit can move by a predetermined welding depth. Such a linear sensor may provide an analog output of the speed change at the same time as the voltage and current analog output of the linear displacement depending on the configuration. For example, in order to detect when the linear sensor touches the object to be welded, the linear sensor not only detects the displacement, but also calculates the velocity using a timer and an arithmetic unit built in the linear sensor, can do.

The linear sensor senses the relative movement of the probe portion and the linear sensor body, and when the horn attaches to the object to be welded and the moving portion of the ultrasonic welding portion and the transfer device hardly moves, there is almost no movement between the probe portion and the linear sensor body portion Therefore, such a change is sensed in the linear sensor, the relative position between the linear sensor body and the probe is recognized and stored at that moment, and the electric signal is sent to the controller unit to cause ultrasonic oscillation. Then, the relative positional change between the sensor main body and the probe is measured from that moment, and when the measured value exceeds a predetermined value preset in the sensor, another electric signal is generated and transmitted again to stop the ultrasonic wave oscillation, The control valve of the pneumatic cylinder of the apparatus is operated.

However, when the linear sensor detects a contact of the horn with the object to be welded separately from the displacement sensor, for example, when the sensor has the impact sensor, the displacement sensor operates only when the sensor detects the distance A measurement may be started and a signal for ultrasonic oscillation may be transmitted. In this case also, when the distance measured by the linear sensor exceeds a predetermined distance, the linear sensor generates a signal and the controller judges that the welding is completed, so that the ultrasonic welding is stopped. It is separated from the fusion object.

In the present invention, the linear sensor may be a non-contact type linear sensor. In the case of the non-contact type, the contact type and the method are different. However, when the laser changes the distance between the sensor and the corresponding portion of the object to be welded, the ultrasonic welding is stopped and the ultrasonic horn is retracted The same thing can be done.

In the present invention, the conveying apparatus may be a linear conveying apparatus using a guide rail and a linear motor, gear means such as rack and pinion, a linear conveying apparatus using an air cylinder or a hydraulic cylinder, or the like.

In the present invention, the rear sensor may also be a position sensor using sensors of various operating principles such as a touch sensor and a photo sensor.

On the other hand, in the fusion welding method using the ultrasonic welding apparatus of the present invention,

A contact step of applying a continuous pressure to the ultrasonic welded portion through the transfer device in a state where the probe is in contact with the fixing portion to advance the horn so as to contact the object to be welded,

The linear sensor recognizes the contact between the horn and the object to be welded through the displacement or speed change with time and generates the first signal to set the contact position to the reference position and to make the ultrasonic vibration in the horn ,

A fusing depth determining step of measuring a movement of the ultrasonic fusing part due to softening and melting of the object to be fused after the oscillating step and generating a second signal by determining whether the value is equal to or greater than a predetermined distance,

And a retracting step of retracting the conveying device so as to separate the horn from the object to be welded.

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above problems of the conventional art, and it is an object of the present invention to provide an apparatus and a method for adjusting a position of a contact, It is an object of the present invention to provide an ultrasonic welding apparatus in which control is performed so as to form a welding depth so that welding can be uniformly performed in a welding object.

FIG. 1 and FIG. 2 are schematic structural diagrams schematically showing an adjacent state as a fusion-bonded object by waiting or moving to perform ultrasonic fusion in an example of a conventional ultrasonic fusion bonding apparatus.
FIG. 3 and FIG. 4 are schematic structural conceptual diagrams showing a state in which an object to be fused is waiting or moving to perform ultrasonic welding in an embodiment of the ultrasonic welding apparatus according to an embodiment of the present invention,
5 is a schematic configuration conceptual diagram illustrating an ultrasonic fusing apparatus according to another embodiment of the present invention,
6 is a perspective view showing an ultrasonic welding apparatus according to another embodiment of the present invention.

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

3 and 4, an ultrasonic welding apparatus including an ultrasonic welding unit 20, a transfer device, a linear sensor, and a rear sensor 60 is disclosed.

The transfer device is provided with a pneumatic cylinder (10). The pneumatic cylinder has a piston, which is not shown but serves as a partition wall in the cylinder as is generally known, and the piston can be moved forward and backward in the cylinder by injecting and recovering air into and into the cylinder at the front and rear ends of the piston An air inlet is installed. A valve (15) for regulating inflow of air is provided near the air inlet.

One side of the cylinder loader (90, 190) is connected to both sides of the piston, and the piston and the cylinder loader (90, 190) move together. The front cylinder loader 90 has a connecting portion at its front portion and an ultrasonic welded portion 20 at its connecting portion to move together with the front cylinder loader 90.

The ultrasonic horn 21 is provided at the front end of the ultrasonic welding unit as in the conventional ultrasonic welding apparatus. Mechanical vibrations are generated in the transducer 23 of the ultrasonic fused portion and the horn 21 touches the fused portion of the fused object to generate vibration between the fused objects and frictional heat due to the vibration.

However, in this embodiment, a linear sensor is coupled to the rear cylinder loader 190, and the linear sensor includes the probe 175 and the main body 170. The end of the probe 175 touches the rear wall 150 fixing the pneumatic cylinder.

The movement of the ultrasonic fused portion 20 coupled with the cylinder loader 90 of the transfer device is started so that the linear sensor starts to operate as a displacement sensor so that the horn reaches the object to be welded 100, The relative position between the main body 170 and the probe 175 at the present time is set as the reference position and the relative positional change between the main body 170 and the probe 175 is measured and the electrical signal is transmitted to the controller unit 200 to cause the controller unit 200 to start the oscillation of the ultrasonic fused portion 20 and start fusion.

The probe 175 of the linear sensor 170 is formed in the shape of a bar or a rod that passes through the sensor body 170. Since the front end of the probe 175 is already in contact with the rear wall 150 when the ultrasonic fused portion 20 starts to advance, the sensor body 170 is moved and fixed without moving, ) And the probe 175, the linear sensor measures whether the linear sensor has moved a certain distance from the reference position.

The cylinder loader 90 of the transfer device and the ultrasonic fused portion 20 coupled to the cylinder loader 90 are slowly moved forward so that the front end of the horn approaches the object to be fused 100, . The driving force or the air pressure of the transfer device is set so that the horn 21 is not strong enough to push the object to be fused and continue to move forward so that the horn 21 is almost stationary at the moment when it touches the object 100 to be fused. The linear sensor senses such a change in displacement amount or speed change of the ultrasonic fused portion 20 so that the linear sensor starts to measure the relative position change from the reference position between the main body 170 and the probe 175.

In addition to a typical LVDT type linear sensor, when a speed change during a short measurement period exceeds a predetermined amount due to a complex sensor configuration, an acceleration sensor or an impact sensor acting separately from the displacement sensor portion in the linear sensor detects the occurrence of the one- And the Lini sensor can recognize the relative position of the main body 170 and the probe 175 at that moment by recognizing the Lini sensor as the start of the relative position change measurement by the previously inputted program and store it as the reference position. At this time, the confirmation of the position may be performed by the recognition device of the main unit reading and recognizing the scale formed on the probe, or various types of recognition devices may be used.

When the one-time signal is transmitted to the controller unit 200, the controller unit 200 automatically activates the oscillation circuit of the ultrasonic fused portion 20 by the built-in program to actuate the horn touching the fusion object 100 Ultrasonic welding is performed.

When ultrasonic welding is performed, the object to be welded 100 is partially softened and melted around the horn 21, and when the continuous pressure of the transfer device is applied through the horn, the softened and melted portion is partially pushed around, You can advance. Therefore, the forward distance of the horn 21 during ultrasonic welding may be a direct measure of the degree of progress of the ultrasonic welding, and if the horn further advances from the reference position through experiment or empirically determined distance, .

A certain distance determined experimentally or empirically is input into the linear sensor through a program in advance and when a certain distance elapses from the measurement start position (reference position) is confirmed through measurement and comparison of the linear sensor, And the controller unit stops the operation (oscillation) of the ultrasonic fusing unit, and the signal is fed back to the conveying device so that the conveying direction of the conveying device is immediately changed and the conveying device is retracted or retracted after a predetermined holding time . When the rear sensor senses the position of the retreating piston or connection and signals the controller unit, the controller unit operates the valve near the inlet of the air flowing into the pneumatic cylinder, and the retraction operation is stopped.

Thereafter, when the fused object is taken out and a new fused object is brought in and placed at the work position, the operator operates the transfer device as in the first operation through the switch operation to advance the horn or the unshown sensor in the work position moves the controller unit It is possible to operate the transfer device by operating it, and the subsequent operations can be repeatedly performed as described above.

FIG. 5 shows an ultrasonic welding apparatus according to another embodiment of the present invention, and FIG. 6 shows an ultrasonic welding apparatus according to another embodiment of the present invention.

Unlike the other embodiments shown in FIGS. 3 and 4, in these embodiments, the linear sensor bodies 270 and 270 'are mounted on the connecting portion 40 and the front ends of the probes 275 and 275' It is fixed to the wall where the stopper was installed.

In addition, the linear sensor is operated to always measure the displacement during operation of the transfer device. That is, the linear sensor always senses the relative movement of the probe 275, 275 'and the linear sensor body 270, 270'. The linear sensor has its own timer and a computing device is provided to calculate the speed and acceleration through displacement with time, and it can also have a function of a speed sensor or an acceleration sensor.

Accordingly, when the ultrasonic welding portion and the moving part of the transfer device are hardly moved due to the horn 21 being attached to the fusion object, the movement between the probe 275 and 275 'and the linear sensor body 270 and 270' So that the relative position between the linear sensor body and the probe is recognized and stored at that moment by sensing the change in operation through the speed sensor of the linear sensor or the acceleration sensor function and the electric signal is sent to the controller unit 200 for ultrasonic oscillation .

The operation and function of the linear sensor and the entire ultrasonic fusing device described below can be similar to the operation of the previous embodiment. That is, the relative positional change between the sensor body and the probe is measured cumulatively from the instant of ultrasonic oscillation, and when the measured value exceeds a predetermined value preset in the sensor, another electric signal is generated and transmitted again to stop the ultrasonic oscillation through the controller unit .

Then, the pneumatic cylinder control valve 15 of the transfer device is operated to retract the ultrasonic welded portion.

In this embodiment, since the linear sensor can recognize and calculate the movement and position of the moving part, that is, the moving part, i.e., the ultrasonic welding part 20, the piston, the cylinder loader 90 and the connecting part, The retraction of the movable part can be stopped by recognizing the retreat point without the need of the retraction.

3 to 5 do not have a separate stopper mechanically restricting the progress of the movable part, but when the linear sensor or the controller unit malfunctions when the probe extension 277 shown in FIG. 6 is provided, It can serve as a mechanical stopper.

In the above embodiments, the components of the linear sensor and the controller unit are separately referred to and the operations are also classified. However, since the functions can be largely overlapped or mixed, it can be understood that the element classification is conceptual. The controller unit or the linear sensor body may be in the form of a computer or in the form of a single microcomputer chip, and the program may be a software program written in hardware such as a nonvolatile memory device or embedded in other storage devices, A predetermined predetermined distance or a retreating point position or the like may be modified depending on the environmental change and the object to be fused.

In the above-described embodiments, the contact type sensor in which the probe is fixed to the linear sensor is described. However, it is also possible to replace the non-contact type sensor or the other known non-contact type sensor that measures the distance by using a laser.

In the structure of the present invention, ultrasonic welding is performed only when the horn comes into contact with the object to be welded, ultrasonic welding is performed, and the movement distance of the horn capable of directly judging the degree of fusion from the reference position stored for measurement is measured, The ground ultrasonic welding is stopped.

Therefore, it is possible to achieve accurate welding regardless of the position of the object to be welded and the position at which the object to be welded and the horn meet, thereby reducing defects due to the welding process.

While the present invention has been particularly shown and described with reference to preferred embodiments thereof, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the scope of the appended claims. Those skilled in the art will appreciate that. Accordingly, all such modifications and equivalents may be resorted to, falling within the scope of the invention.

10: Pneumatic cylinder 15: Valve
20: ultrasonic fused portion 21: horn
23: Converter
50: guide portion 60: rear sensor
70: front sensor 80: stopper
90, 190: cylinder loader 100: object to be fused
170, 270, 270 ': (Linear sensor)
175, 275, 275 ': probe
200: controller unit

Claims (6)

An ultrasonic welding portion including a horn,
A transfer device connected to the ultrasonic fused portion for transferring the ultrasonic fused portion,
The ultrasonic welding apparatus according to any one of claims 1 to 3, wherein the ultrasonic welding apparatus further comprises: an ultrasonic welding unit for generating ultrasonic welding; And a linear sensor for sensing the movement of the predetermined distance to stop the operation of the ultrasonic welding unit and generating a retraction signal for retracting the transfer device when a predetermined distance is progressed. The method according to claim 1,
Further comprising a rear sensor for sensing a retracted position of the ultrasonic welding unit and stopping the retraction of the transfer device. The method according to claim 1,
And a controller unit electrically connected to the linear sensor, the transfer device, and the ultrasonic fused portion so as to operate the transfer device and the ultrasonic fused portion through an electric signal of the linear sensor. The method according to claim 1,
Wherein the linear sensor comprises a probe which is fixed at the time of measurement of the displacement when the attachment is in contact with the stationary part, and a body movable relative to the probe,
Wherein the main body includes an acceleration sensor or a velocity sensor capable of generating an electric signal by detecting a change in a moving state of the ultrasonic welding apparatus. In the fusion welding method using the ultrasonic welding apparatus according to claim 4,
A contact step of applying a continuous pressure to the ultrasonic welded part through the transfer device while the probe is in contact with the fixed part so that the horn is moved forward to contact the object to be fused;
The linear sensor recognizes the contact by the acceleration sensor or the velocity sensor and generates a first signal to set the contact position to a reference position and to cause ultrasonic vibration in the horn,
A fusing depth determining step of measuring the movement of the ultrasonic fusing part by softening and melting of the object to be fused after the oscillating step and generating a second signal by determining whether the value is equal to or greater than a predetermined distance,
And a retracting step of retracting the transferring device so that the horn is spaced apart from the object to be fused. 6. The method of claim 5,
Wherein the acceleration sensor or the velocity sensor is formed by combining a displacement sensor in the linear sensor, a timer, and an arithmetic unit.

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