JP2011206808A - Welding equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To give no damage or the like to a workpiece even if moving speed of a horn is increased in an ultrasonic welding apparatus, to facilitate adaptability to a change in the type of workpiece to deal with, and to apply always constant pressure in the occurrence of deformation of a material during welding and cope with a variety of workpieces.SOLUTION: A driving part for moving a horn 14 of an ultrasonic welding apparatus 1 is designed to be a combination of a stepping motor 7 and a ball screw part 8, with an air buffer 13 installed between the ball screw part 8 and the horn 14, thereby facilitating adjustment of the moving speed or moving amount of the horn 14 and the pressure to a workpiece.

Description

  The present invention relates to a welding apparatus that performs welding while applying pressure to a workpiece, such as an ultrasonic welding apparatus or a spot welding apparatus.

  Conventionally, for example, in a welding technique in which a workpiece is sandwiched between a horn and an anvil or a pair of electrodes, such as ultrasonic welding and spot welding, and ultrasonic vibration or a large current is applied while applying a certain pressure to the workpiece, the horn The air cylinder is widely used when the electrode (work contact member) on one side is moved toward and away from the work or when the work is pressurized (see, for example, Patent Document 1). In this case, a technique in which the entire unit including the workpiece contact member is moved toward and away from the entire unit by a cam mechanism, and pressurization by the workpiece contact member is performed by an air cylinder (for example, see Patent Document 2 and Patent Document 3). ), A technique for applying pressure with the pressure of a spring (for example, see Patent Document 4), and a technique for applying pressure to a workpiece by using a lever action by a weight (for example, a special technique). Document 5 reference.) Are also known.

Japanese Patent Laid-Open No. 11-20024 JP-A-11-28767 JP 2003-127234 A JP 2001-105160 A JP 2008-1037 A

  However, with the conventional method of using the air cylinder to move or press the workpiece contact member and pressurize, for example, it is not appropriate to apply an excessive force to the workpiece even though the approach / release stroke is large. However, since the approach speed cannot be increased, there is a problem that it takes a long time to move until welding and the work efficiency is poor. In addition, when pressurizing the workpiece, the technology that uses the spring force or the lever force is that the welding force is likely to change when the workpiece being welded is deformed and the thickness is displaced, and the welding quality is not stable. In order to change the applied pressure, the spring and weight must be replaced, which is inconvenient when handling a wide variety of workpieces.

  Therefore, the present invention does not damage the workpiece even if the moving speed of the workpiece abutting member for applying pressure to the workpiece is increased and the workpiece can be approached / removed. Even if it is changed, it can be easily handled, and even when the material is deformed during welding, a constant pressure can always be applied to keep the welding quality constant, and the pressure applied to the workpiece can be changed. The purpose is to be able to make it.

  In order to achieve the above object, the present invention places a work on a receiving member, makes a work contact member driven by a driving means approach and contact the work, and moves the work with the work contact member. In the welding apparatus that is welded while being pressurized, an air buffer is interposed between the driving means and the workpiece contact member or between the receiving member and the mounting member to which the receiving member is attached. .

  That is, for example, in ultrasonic welding, a work is placed on an anvil as a receiving member, and a horn as a work abutting member is moved toward the work so as to approach and come into contact with the work. In spot welding, the workpiece is sandwiched between the electrode on one side as the receiving member and the electrode on the other side as the workpiece abutting member, and the workpiece is added via the workpiece abutting member by driving means or the like. In this case, the work contact member is moved between the driving means and the work contact member or between the receiving member and the mounting member to which the support member is attached, so that the work contact member is moved to the work piece. The impact at the time of contact with the workpiece can be reduced, and the workpiece contact member can be moved at a high speed. Further, even when the workpiece is deformed during welding, the air buffer absorbs the displacement, so that pressurization of the workpiece by the workpiece contact member is more stable.

  In this case, the air shock absorber is a device that uses the elastic force of air to mitigate the impact. For example, when the workpiece contact member is moved toward the workpiece, it is sealed according to the stroke amount. A type in which air is introduced into the space to obtain an impact mitigation effect is applicable.

  Further, if the driving means is a combination of a pulse control type motor and a ball screw, the moving speed and moving stroke of the workpiece contact member can be easily adjusted. For example, the distance between the workpiece contact member and the workpiece is increased. In such a case, the workpiece abutting member is moved at a high speed, and when approaching, the control can be easily performed so as to switch to a low speed, and the air buffer is arranged between the drive unit and the workpiece abutting member. In such a case, by combining with an air shock absorber, it becomes possible to easily adjust the pressing force of the workpiece contact member against the workpiece, and it is possible to easily cope with welding of various types of workpieces. That is, when it is desired to increase the applied pressure, the supply air pressure is set high, and when it is desired to decrease the applied pressure, the supply air pressure may be set low. If you want to increase the applied pressure, set the movement stroke control value of the workpiece contact member to a larger value. If you want to decrease the applied pressure, set the movement stroke control value of the workpiece contact member to a smaller value. .

  In a welding apparatus in which a workpiece is sandwiched between a receiving member and a workpiece abutting member and welded while pressurizing the workpiece with the workpiece abutting member, or between the driving means and the workpiece abutting member, or the receiving member and the receiving member are attached. By interposing an air shock absorber between the workpiece contact member and the workpiece, the impact when the workpiece contact member comes into contact with the workpiece can be mitigated, the workpiece contact member can be moved at high speed, and welding can be performed. Even when the middle workpiece is deformed, the pressure applied to the workpiece can be kept constant and the welding quality can be improved. In addition, if the drive means is a combination of a pulse control motor and a ball screw, the moving speed of the workpiece contact member can be adjusted easily and precisely. In the case where it is arranged between the members, it is possible to adjust the pressure applied to the workpiece, and it is possible to easily cope with changes in the type of workpiece to be handled.

It is a general view which shows an example at the time of applying the welding apparatus which concerns on this invention as an ultrasonic welding machine. It is explanatory drawing which shows an example of the air shock absorber applied to this invention.

An example of a welding apparatus according to the present invention will be described with reference to the accompanying drawings.
The welding apparatus according to the present invention allows the workpiece to be handled without causing damage to the workpiece even when the moving speed of the workpiece abutting member for applying pressure to the workpiece is increased. Even if the type of material is changed, it is possible to improve the welding quality by always applying a constant pressure even when the material is deformed during welding. Applied to sonic welding equipment.

  This welding apparatus is particularly effective for a conductor having a thin thin conductor or a narrow conductor. For example, a conductor of a rotary connector (copper foil having a thickness of about 35 microns and a width of about 1.6 mm) and a terminal (made of copper) ), This conductor is a flat cable coated with resin, the coating of only the welded part is removed and the conductor is exposed, and the periphery of the welded part is surrounded by a resin mold, The terminal is overlapped and welded to this part. At this time, the conductor portion is easily broken, but the welding apparatus of the present invention is capable of reliably welding without breaking the conductor portion.

  That is, as shown in FIG. 1, the present welding apparatus 1 includes a support base 3 erected near one side of the base 2 and a slide base 4 provided so as to be horizontally movable near the other side of the base 2. An anvil mounting member 5 to which an anvil 6 is mounted is fixed on the slide table 4, and a pulse control type stepping motor 7 as a driving means is provided on the support table 3. A ball screw portion 8 is provided on the motor shaft that is attached with the shaft in the vertical direction and extends downward from the stepping motor 7. The lower end portion of the ball screw portion 8 is supported by a bearing member 9 that projects forward from the support base 3.

  A female screw member 11 is screwed into an intermediate portion of the ball screw portion 8, and an air shock absorber 13 is connected to the female screw member 11 via a connecting member 12 extending downward. A horn 14 as a workpiece contact member that contacts the workpiece and applies ultrasonic vibration is connected to the lower side of the vessel 13.

For this reason, when the stepping motor 7 is operated and the ball screw portion 8 is rotated, the horn 14 is moved up and down via the female screw member 11, the connecting member 12, the air shock absorber 13, etc., and the workpiece placed on the anvil 6 is moved. On the other hand, the tip of the horn 14 can be freely approached, abutted, and detached.
The slide table 4 is slidable in the direction perpendicular to the paper surface of FIG. 1. For example, a plurality of workpieces are set at predetermined intervals in the direction perpendicular to the paper surface on the anvil 6 and correspond to the lower part of the horn 14. When the welding of the workpieces to be completed is completed, the slide table 4 is sequentially slid and the next workpiece is moved below the horn 14 so that the welding operation is efficiently performed on all the workpieces.

  As the air shock absorber 13, an air shock absorber that uses an elastic force of air can be applied. In this embodiment, an air spring (product name 2M2A) manufactured by Bridgestone Corporation is used. As shown in FIG. 2, the air buffer 13 is configured such that air flows into the sealed space portion 16 as the horn 14 is lowered and exhibits a buffering effect. When the horn 14 is lowered to a certain position, Thereafter, the workpiece can be pressurized with a uniform pressure.

An example of operation control in the welding apparatus 1 as described above will be described.
A rotating connector conductor (copper foil) and a copper terminal are set on the anvil 6 as a workpiece, the stepping motor 7 is operated as a drive source, and the horn 14 is lowered via the ball screw portion 8. At this time, the first descending stroke is moved at a high speed of about 60 mm / s, moved at a low speed of about 20 mm / s before the horn 14 contacts the workpiece, and finally moved by the action of the air buffer 13. When the horn 14 contacts the workpiece, the workpiece is prevented from being damaged, and when the bottom dead center of the horn 14 is detected, the operation of the stepping motor 7 is stopped. In this state, the pressure applied to the workpiece is kept constant by the air buffer 13.

Then, the workpiece is welded by applying ultrasonic vibration to the workpiece through the horn 14. At this time, even when the workpiece is deformed, the displacement in the thickness direction is absorbed by the air buffer 13, and the pressure applied to the workpiece is Since it is kept constant, the welding quality is good.
When the welding is completed, the motor 7 is operated to raise the horn 14, and when the top dead center of the horn 14 is detected, the driving of the motor 7 is stopped. When the slide table 4 slides and the next workpiece comes downward, the same procedure is repeated.

In the manner as described above, even if the moving speed of the horn 14 is set to a high speed, damage to the work is suppressed by the action of the air buffer 13, and in the conventional case, the tact time for moving the horn 14 is 2.25. What is required about 2 sec / ch can be reduced to about 1 sec / ch, and the air buffer 13 can absorb the displacement in the thickness direction due to material deformation during welding, so the pressure applied to the workpiece is constant. The welding quality can be improved.
Further, since the stepping motor 7 and the ball screw portion 8 are combined to move the horn 14, the moving speed can be easily converted and the movement can be accurately controlled.

  Further, when the mounting position of the air shock absorber 13 is between the horn 14 and the ball screw portion 8, the applied pressure can be adjusted by setting the supply air pressure. Further, by adjusting the descending stroke control value of the horn 14, the pressure applied to the workpiece can be easily adjusted. That is, when it is desired to increase the applied pressure, the supply air pressure is set high, and when it is desired to decrease the applied pressure, the supply air pressure may be set low. Further, when it is desired to increase the applied pressure, the descending stroke control value of the horn 14 by the stepping motor 7 or the ball screw portion 6 is increased, and when it is desired to decrease the applied pressure, the decreased stroke control value of the horn 14 is decreased. .

In the above embodiment, the air buffer 13 is provided between the stepping motor 7 or the ball screw portion 8 and the horn 14, but may be provided between the anvil 6 and the anvil mounting member 5.
In this embodiment, the case of an ultrasonic welding machine as the welding apparatus has been described as an example. However, the present invention can be applied to spot welding as well as the ultrasonic welding machine.

  In devices that weld workpieces while pressurizing workpieces, such as ultrasonic welding equipment and spot welding equipment, tact time can be shortened, and at the same time welding quality can be improved, so widespread use is expected. .

DESCRIPTION OF SYMBOLS 1 ... Welding apparatus, 7 ... Stepping motor, 8 ... Ball screw part, 13 ... Air buffer, 14 ... Horn.

Claims (2)

A welding apparatus in which a workpiece is placed on a receiving member, a workpiece abutting member driven by driving means is approached and abutted toward the workpiece, and the workpiece is welded while being pressed by the workpiece abutting member. The welding apparatus is characterized in that an air buffer is interposed between the driving means and the workpiece contact member or between the receiving member and an attachment member to which the receiving member is attached. 2. The welding apparatus according to claim 1, wherein the driving means is a combination of a pulse control type motor and a ball screw.

Images