JP2011020153A - Soldering device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a soldering device which can realize a highly reliable joint by controlling the height of a liquid surface of molten solder to suppress a soldering failure. <P>SOLUTION: A soldering device 1 is a device in which a soldering object 10 is immersed in molten solder 2a and comprises a non-contact displacement gauge 3 that, in a state of non-contacting with the molten solder 2a, measures the height of a liquid level LS of the molten solder 2a, and a movement mechanism 5 that, based on the height of the liquid level LS measured with the non-contact displacement gauge 3, the travel distance of the soldering object 10 is controlled so that the soldering object 10 is immersed in the molten solder 2a. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a soldering apparatus, and more particularly to a soldering apparatus for immersing an object to be soldered in molten solder.

  As one of the soldering methods, there is an immersion soldering method. In the immersion soldering method, soldering is performed by immersing an object to be soldered in molten solder.

  For example, when an electronic component (resistor, capacitor, IC (Integrated Circuit), etc.) is electrically connected to a printed wiring board, an immersion soldering method is employed. Specifically, in a soldering apparatus, an electronic component is soldered to the printed wiring board by immersing the printed wiring board on which the electronic component is disposed in molten solder stored in a solder bath.

  In this soldering apparatus, the printed wiring board on which the electronic components are arranged moves relative to the molten solder, so that the printed wiring board contacts the liquid surface of the molten solder. Thereby, a solder joint part is formed in the part which contacted the liquid level of the molten solder of the printed wiring board.

  The quality of the solder joint is affected by the liquid level of the molten solder. That is, for example, when the liquid level of the molten solder is low, the printed wiring board does not contact or does not sufficiently contact the molten solder, so that soldering defects such as unsoldering and insufficient soldering occur. Therefore, a good solder joint cannot be obtained.

  Therefore, in order to obtain a good solder joint, it is extremely important to manage the liquid level of the molten solder.

  As an example of managing the height of the molten solder surface, for example, Japanese Patent Laid-Open No. 8-309520 (Patent Document 1) discloses that the float provided on the molten solder surface is moved up and down even when the molten solder surface level changes. A jet-type soldering apparatus is disclosed in which the molten solder outflow portion formed at the upper end of the vertical moving plate is always kept at a certain height from the molten solder surface by moving up and down together with the moving plate.

JP-A-8-309520

  However, in the jet type soldering apparatus of the above publication, dross (solder oxide) or flux residue that floats on the surface of the molten solder adheres to the float, so that the liquid level of the molten solder in the float can be increased. The followability is poor and it is difficult to control the height of the liquid level of the molten solder.

  The present invention has been made in view of the above problems, and its purpose is to obtain a highly reliable solder joint by controlling the liquid level of the molten solder and suppressing soldering defects. It is providing the soldering apparatus which can be performed.

  The soldering apparatus of the present invention is a soldering apparatus for immersing an object to be soldered in molten solder, for measuring the liquid level of the molten solder in a non-contact state with respect to the molten solder. A non-contact displacement meter, and a moving mechanism that controls the amount of movement of the soldering object so that the soldering object is immersed in the molten solder based on the liquid level measured by the non-contact displacement meter. I have.

  According to the soldering apparatus of the present invention, the moving amount of the soldering object is controlled so that the soldering object is immersed in the molten solder based on the liquid level measured by the non-contact displacement meter. Therefore, since the soldering object can be reliably brought into contact with the molten solder, a highly reliable solder joint can be obtained by suppressing soldering defects.

It is a fragmentary sectional view showing roughly the soldering device in one embodiment of the present invention. It is a fragmentary sectional view which shows roughly the soldering apparatus in one embodiment of this invention, Comprising: It is a figure which shows the state by which the soldering target object was immersed in the molten solder.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
Initially, the structure of the soldering apparatus of one embodiment of this invention is demonstrated.

  Referring to FIG. 1, a soldering apparatus 1 according to an embodiment of the present invention mainly includes a solder bath 2, a non-contact type displacement meter 3, a control unit 4, a moving mechanism 5, and a wiper 6. is doing. In addition, in FIG. 1, the molten solder 2a, the printed wiring board 10a which is an example of the soldering target object 10, and the electronic component 10b are also illustrated.

  The soldering apparatus 1 is an apparatus for immersing the soldering object 10 by immersing it in the molten solder 2 a stored in the solder bath 2.

  The solder tank 2 is constituted by a hollow casing having at least a part of the upper surface opened. Molten solder 2a is stored inside the casing.

  Above the molten solder 2a, a non-contact displacement meter 3 for measuring the height of the liquid level LS of the molten solder 2a in a non-contact state with respect to the molten solder 2a is disposed. The non-contact type displacement meter 3 is disposed at a predetermined interval from the liquid level LS of the molten solder 2a and is not in contact with the liquid level LS. The non-contact type displacement meter 3 is connected to the control unit 4. For example, an eddy current displacement meter can be applied to the non-contact displacement meter 3. Since the eddy current displacement meter can be used for high-temperature objects, it can be used for molten solder.

  A control unit 4 for controlling the amount of movement of the moving mechanism 5 based on the height of the liquid level LS of the molten solder 2 a measured by the non-contact displacement meter 3 is connected to the moving mechanism 5. The control unit 4 is configured to control the amount of movement of the soldering object 10 by feeding back the height of the liquid level LS measured by the non-contact displacement meter 3 to the motor 5a of the moving mechanism 5. .

  Above the molten solder 2a, a moving mechanism 5 for immersing the soldering object 10 in the molten solder 2a based on the height of the liquid level LS measured by the non-contact displacement meter 3 is disposed. The moving mechanism 5 mainly includes a motor 5a, a shaft 5b, an attachment member 5c, a gripping member 5d, and a cover member 5e. The moving mechanism 5 is configured to be movable in a direction (an arrow A direction in the figure) in which the soldering object 10 is immersed in the molten solder 2a by the driving force of the motor 5a. The motor 5a is configured to move in a direction in which the attachment member 5c is immersed in the molten solder 2a via the shaft 5b. A cover member 5e is supported on the attachment member 5c via a gripping member 5d. The printed wiring board 10a and the electronic component 10b, which are examples of the soldering object 10, are supported by the gripping member 5d and the cover member 5e so as to be movable in the direction of immersion in the molten solder 2a. The driving force of the moving mechanism 5 is not limited to the motor as long as the object to be soldered can be moved, and an air cylinder or the like can also be applied.

  A wiper 6 for removing solder oxide (dross) 7 floating on the surface of the molten solder 2 a is disposed inside the solder bath 2. The wiper 6 is configured to be movable in the direction along the liquid level LS (in the direction of arrow B in the figure) in the vicinity of the liquid level LS of the molten solder 2a. The wiper 6 may be configured to be movable so as to retract above the molten solder 2a. The non-contact type displacement meter 3 is arranged above an operation range surface that is a surface constituted by the movement range of the wiper 6 in plan view.

  For example, Sn (tin) -3.0Ag (silver) -0.5Cu (copper), which is a general lead-free solder material, can be applied to the molten solder 2a. For example, a substrate in which an epoxy resin is contained in a glass cloth can be applied to the printed wiring board 10a.

Next, operation | movement of the soldering apparatus of one embodiment of this invention is demonstrated.
With reference to FIGS. 1 and 2, a printed wiring board 10a and an electronic component 10b are prepared as an example of a soldering object. The printed wiring board 10a and the electronic component 10b are supported by the holding member 5d and the cover member 5e, and are disposed above the molten solder 2a.

  The non-contact displacement meter 3 measures the height of the liquid level LS of the molten solder 2a. Based on the height of the liquid level LS of the molten solder 2 a measured by the non-contact displacement meter 3, the control unit 4 controls the moving amount of the moving mechanism 5. More specifically, for example, information on the measured value of the height of the liquid level LS measured by the non-contact displacement meter 3 is sent to the control unit 4. The controller 4 feeds back the information to the amount of movement of the shaft 5b by driving the motor 5a. In this way, the moving amount of the moving mechanism 5 is controlled.

  Thereby, the printed wiring board 10a and the electronic component 10b supported by the moving mechanism 5 are soldered with an appropriate amount of solder by contacting the molten solder 2a stored in the solder bath 2 with an appropriate amount of movement. .

  Further, the printed wiring board 10a, the electronic component 10b, and the cover member 5e are lowered and immersed in the molten solder 2a, whereby the liquid level LS of the molten solder increases by the volume of the immersion. Since the non-contact displacement meter 3 measures the height of the liquid level LS, the rise of the liquid level LS is fed back to the lowering operation (lowering height) of the printed wiring board 10a and the electronic component 10b. Thereby, the printed wiring board 10a and the electronic component 10b move following the fluctuation in the height of the liquid level LS due to the printed wiring board 10a, the electronic component 10b, and the cover member 5e being immersed in the molten solder 2a.

  In addition, the wiper 6 moves in the vicinity of the liquid level LS of the molten solder 2a in a direction along the liquid level LS, so that the dross 7 which is an oxide of solder floating on the surface of the molten solder 2a is removed.

Next, the effect of the soldering apparatus of one embodiment of the present invention will be described.
According to the soldering apparatus 1 of one embodiment of the present invention, the soldering object 10 is changed to the molten solder 2a based on the height of the liquid level LS of the molten solder 2a measured by the non-contact displacement meter 3. The amount of movement of the soldering object 10 is controlled so as to be immersed. For this reason, the height of the liquid level LS measured by the non-contact type displacement meter 3 is fed back to the movement amount of the soldering target object 10, so that the soldering target object 10 can be reliably secured even when the liquid level LS fluctuates. It can be made to contact the molten solder 2a. As a result, a highly reliable solder joint can be obtained by controlling the height of the liquid level LS of the molten solder 2a and suppressing the occurrence of soldering defects such as unsoldering and insufficient soldering.

  Moreover, when the soldering object 10 is immersed in the molten solder 2a, the liquid level LS rises by the immersed volume. According to the soldering apparatus of one embodiment of the present invention, the soldering object 10 can be moved following the variation in the height of the liquid level LS due to the immersed volume. Thereby, since the fluctuation | variation of the height of the liquid level LS by this immersed volume can also be tracked, the soldering target object 10 can be made to contact the molten solder 2a more reliably.

  In addition, when the support member etc. which support the soldering target object 10 are immersed in the molten solder 2a, the liquid level LS rises together with the volume of the immersion of the support member. According to the soldering apparatus of one embodiment of the present invention, the soldering object 10 can be moved following the fluctuation of the height of the liquid level LS due to the immersed volume of the support member or the like. Thereby, also in this case, the soldering object 10 can be more reliably brought into contact with the molten solder 2a.

  Moreover, since an eddy current displacement meter can be used with respect to a high temperature target object, it can be used with respect to molten solder. Therefore, the liquid level LS of the molten solder 2a can be reliably measured. Thereby, the soldering target object 10 can be made to contact the molten solder 2a reliably.

  Further, the non-contact type displacement meter 3 is installed above the operation range surface of the wiper 6. For this reason, since the dross 7 is removed by the wiper 6, the non-contact displacement meter 3 can measure the height of the liquid level LS of the molten solder 2a without being affected by the dross 7. Thereby, the height of the liquid level LS of the molten solder 2a can be measured with higher accuracy. Thereby, the soldering object 10 can be made to contact the molten solder 2a more reliably.

  In addition, although the above demonstrated the case where the base material which made the glass cloth contain the epoxy resin was applied as an example of a printed wiring board, it is not limited to this, A printed wiring board has insulation. For example, a base material made of a material such as a glass nonwoven fabric or a paper base material containing a polyimide resin or a phenol resin may be applied.

  Moreover, although Sn-Ag-Cu type solder was demonstrated as an example of solder in the above, it is not limited to this, Sn-Cu type solder, Sn-Bi (bismuth) type solder, Sn-In (indium) ) Based solder, Sn—Sb (antimony) based solder, or Sn—Pb (lead) based solder may be applied.

  In the above description, the non-contact displacement meter has been described for measuring the height of the molten solder liquid level. This means that the position of the molten solder liquid level for moving the soldering object is measured. It is. Therefore, for example, measuring the position of the liquid surface of the molten solder by measuring the distance from the liquid surface of the molten solder to the displacement meter is also included.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  DESCRIPTION OF SYMBOLS 1 Soldering apparatus, 2 Solder tank, 2a Molten solder, 3 Non-contact displacement meter, 4 Control part, 5 Moving mechanism, 5a Motor, 5b Axis, 5c Mounting member, 5d Holding member, 5e Cover member, 6 Wiper, 7 Solder oxide (dross), 10 soldering object, 10a printed wiring board, 10b electronic component, LS liquid level.

Claims (3)

A soldering apparatus for immersing an object to be soldered in molten solder,
A non-contact displacement meter for measuring the liquid level of the molten solder in a non-contact state with respect to the molten solder;
A moving mechanism that controls the amount of movement of the soldering object so that the soldering object is immersed in the molten solder based on the height of the liquid level measured by the non-contact displacement meter. , Soldering equipment.   The soldering apparatus according to claim 1, wherein the non-contact type displacement meter is an eddy current displacement meter. A wiper for removing oxide on the liquid surface of the molten solder;
3. The soldering apparatus according to claim 1, wherein the non-contact type displacement meter is installed above an operation range surface of the wiper.

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