JPH0218947B2 - - Google Patents

Description

[Detailed Description of the Invention] <<Field of Industrial Application>> The present invention relates to a method for soldering multi-terminal chip components to predetermined locations on a printed wiring board, and a soldering iron used directly to carry out this method. .

<<Prior art>> Conventional soldering methods include the so-called reflow method and the dip method. In these methods, the following steps are taken in the process of soldering chip parts. ing.

That is, when using the reflow method, cream solder is applied to predetermined locations on the printed wiring board using an automatic printer or the like, and then an automatic loading machine is used to apply the cream solder to the preliminary solder locations.
A necessary number of various predetermined chip parts are placed over each other, and while maintaining this state, the entire printed wiring board is placed in an automatic reflow oven, where the cream solder is melted by infrared heating, etc., and then cooled in air. By solidifying, all the chip parts mentioned above can be reflow soldered at once.

Therefore, when using the above-mentioned reflow method, not only is it necessary to invest a large amount of equipment in automatic mounting machines and automatic reflow ovens, but also the chip parts placed across the preliminary soldering area may be damaged due to external forces such as vibrations. Misalignment may occur, resulting in incorrectly connected soldering, which can be quite troublesome to repair later, and the entire chip component is heated in the automatic reflow oven. As a result, there are disadvantages such as an adverse thermal effect on the component.

Next, as is known, the method for soldering chip parts by the dip method described above involves applying cream solder to a predetermined position on a printed wiring board in advance, and applying an adhesive onto the board.
The chip parts to be soldered are bonded onto the adhesive using an automatic loading machine, and then heated in a heating furnace to harden the adhesive, thereby solidifying the bonded state of the parts, It maintains its immovable state even when subjected to external vibrational force or when the printed wiring board is turned upside down.Then, by heating it at high temperature with a soldering iron, etc., the cream solder is melted, and this is air-cooled and solidified. be.

For this reason, the dip method requires more equipment than the reflow method, requires a large investment in equipment, and also requires an adhesive application process in addition to applying cream solder. Furthermore, since a heating operation is required to cure the adhesive, a considerable amount of time and effort is required for soldering, which is not only inefficient, but also requires heating and cooling of the adhesive. Due to such factors, expansion and contraction occur during the hardening period, and at this time the chip parts may shift from their designated positions, making the arrangement of the chip parts uneven and reducing the product value. , there is a drawback that it is necessary to check this and make adjustments to correct the position.

Therefore, the applicant has already proposed the following soldering method in order to eliminate the deficiencies of the above-mentioned conventional method.
(Japanese Patent Application No. 61-221559) In other words, after a chip component, etc. is sucked up by a transfer suction nozzle pipe, the component is sandwiched from left and right by a pair of heated clamping arms of a soldering iron. The component is placed in a predetermined position on a printed wiring board in this state, and the preliminary solder applied on the board is melted and solidified by air cooling. This allows a large number of components to be soldered in a short period of time, while always ensuring the desired direction of soldering to prevent misalignment.In addition, chip components can only be heated locally to prevent adverse thermal effects on the components. This is a soldering method that not only attempts to reduce the amount of soldering, but also prevents chips from being accidentally dropped during the transfer process.

However, although the above proposal can be used to solder chip components and obtain good results, as shown in FIG. Terminal c, c...,
In the case of a multi-terminal chip part A in which c', c'... are made to protrude outward, unlike the case of a chip part without such multi-terminals, heating clamping arms that simply hold the chip part A are used. In addition to being unable to handle the terminals of such multi-terminal chip components,
They are often deformed by external forces during transportation or handling, and as a result, the distances between the terminals become uneven, or they are distorted in the vertical direction, so even if you try to solder them as they are, the print It is not possible to accurately arrange the terminals at the specified positions on the wiring board, and therefore, conventionally, as a pre-process, the irregular shape of the terminals has been corrected, but this not only requires a great deal of time and effort, but also Correct alignment is difficult to obtain, and in the case of such multi-terminal chip components, it is troublesome to position them at predetermined positions on the printed wiring board, not only by visual inspection but also by computer alignment. There are problems.

<<Problems to be Solved by the Invention>> The present invention has been studied in view of the above-mentioned deficiencies of the conventional method. In the first invention related to the method, the soldering iron has a concave groove for a terminal in a comb-like shape. By using the provided heated clamping arm, the terminal form of a multi-terminal chip component can be easily and accurately corrected in a short time using the soldering iron, the receiving plate of the terminal correcting device, and the correcting guide mechanism. In addition, by using the soldering iron and the transfer suction nozzle pipe, the corrected multi-terminal chip component can be safely and reliably transferred to the desired position, and furthermore, by using the soldering guide mechanism,
To quickly and accurately place the multi-terminal chip component in a predetermined position on a printed wiring board,
Furthermore, by utilizing the transfer suction nozzle pipe, it is possible to perform soldering quickly and reliably.

Further, a second invention relates to a soldering iron suitable for carrying out the soldering method according to the first invention, in which a guide hole is vertically provided in the base body, and the above-mentioned correction guide mechanism and soldering iron are provided. In addition to making the guide mechanism operate smoothly, the terminal groove of the heating clamping arm is shaped into an appropriate L-shape, so that the clamping arm can correct malformed terminals and perform soldering. The purpose is to make it possible to do both.

<<Means for Solving the Problems>> The soldering method according to the first invention of the present application is characterized in that a group of terminals in which a plurality of terminals are extended in parallel outward from a component body is formed in a predetermined number of pairs. Place the provided multi-terminal chip component in the receiving recess of the receiving board of the terminal straightening device, and by fitting the component body, the terminal group is arranged on the straightening upper surface of the receiving board, A separately prepared soldering iron is lowered by the straightening guide mechanism of the terminal straightening device, and the terminal group is clamped by the heated clamping arms provided in the required number of pairs of soldering irons, and the terminal group is held at the lower end of the clamping arm. One terminal is inserted into each of the formed comb-shaped grooves for terminals, and each terminal is pressed against the straightening upper surface of the receiving plate by the back surface of the groove for terminals. Then, the terminal form of the terminal group is corrected, and the suction nozzle pipe for transporting the soldering iron, which can freely suck air, is lowered at the appropriate time, and its lower end nozzle portion is brought into contact with the upper surface of the component body, thereby correcting the corrected terminal form. The multi-terminal chip component is sucked, and under the sucked state, the soldering iron heated with electricity is lowered by the soldering guide mechanism at appropriate times while maintaining the clamped state by the heated clamping arms, so that the soldering iron is lowered onto the printed wiring board. The device is placed in a predetermined position and pressed across a plurality of preliminary solder spots that have been previously attached to the printed circuit, and the preliminary solder is melted by heat conduction through the rear surface of the holding arm. Then, the heating clamping arm is separated from the terminal group of the multi-terminal chip component while the component main body is kept pressed by the transfer suction nozzle pipe, and after the molten preliminary solder begins to harden, the transfer suction nozzle This is because the nozzle pipe is raised so that its lower end nozzle part is separated from the main body of the component.

Next, the soldering iron according to the second invention of the present application has a base body having a plurality of vertically arranged guide holes, a suction nozzle pipe for transfer that can be raised and lowered, and a lower end nozzle section of the suction nozzle pipe for transfer. The heating clamping arm is provided with one or more pairs of heating clamping arms that can be opened and closed laterally, and the lower end of the heating clamping arm is provided with a comb tooth in which a plurality of recessed grooves for terminals are provided at predetermined intervals in the lateral direction. In addition to forming the terminal groove into a mold, the terminal groove is curved into an L-shape with a vertical groove opening inward and a horizontal groove opening downward, so that the vertical groove has a downward facing top surface. This is because an inward facing side surface is formed, and a downward facing back surface is formed in the horizontal groove part.

<<Example>> The present invention will be explained in detail below with reference to the drawings.

First, the soldering iron of the second invention, the terminal straightening device, and the soldering guide mechanism used to carry out the method of the first invention will be described in detail.

The soldering iron 1 has a rectangular parallelepiped-shaped base 2, and in the illustrated example, not only a pair of left and right heating clamping arms 3, 3 but also a pair of front and rear heating clamping arms 3, 3 extend downward facing each other, and the upper end thereof The portion 3a is located in the base body 2 and is configured to be able to laterally move the pair of heating clamping arms 3, 3, 3, 3 in the directions of arrows d and d', respectively, by an operating mechanism (not shown).

Further, in the center of this base body 2, a suction nozzle pipe 4 for transfer is installed so as to be able to move up and down as shown by arrows e and e'.
The lower end nozzle portion 4a of the heating clamping arm 3,
It will move up and down at the center of the space surrounded by 3, 3, 3, and in the figure, 5, 5... is the base 2
A guide hole is shown which is provided through the corner of the square at the apex position of the rectangle and is used when connecting the terminal correction device 12 and the soldering guide mechanism 16, which will be described later.

Now, each of the heating clamping arms 3, 3, 3, 3 is not only equipped with an electric heater (not shown) and can be electrically heated at any time, but also made of a thick plate made of copper or the like. In the heating clamping arms 3, 3, a plurality of grooves 6, 6 for terminals, each of which opens toward the inside and the bottom, are formed so as to have the same width and are spaced apart in the longitudinal direction by a predetermined interval. As a result, the heating clamping arms 3, 3 are finished in a comb-teeth shape as a whole.

That is, as clearly shown in FIG. 6b, the terminal groove 6 is curved into an L-shape with a vertical groove 6a opening inward and a lateral groove 6b opening downward. The horizontal groove portion 6b has a downward facing top surface 6c.
and an inward facing side surface 6d, and a downward facing back surface 6e is formed in the lateral groove portion 6b.

Furthermore, as clearly shown in FIGS. 5 and 6, a non-solder adhesion layer 3b is formed on the iron tip of the heating clamping arm 3 by chromium plating or the like, and a solder-free layer 3b is formed on the back surface 6e of the lateral groove 6b. It is preferable to form a solder adhesive layer 3c by nickel plating or the like, and H in FIG. 6a indicates molten solder adhered to the solder adhesive layer 3c.

Here, FIG. 7 shows a different heating clamping arm 3, and in the above-mentioned embodiment, in order to form the groove 6 for the terminal, the lower end of the thick copper plate is cut or cast. On the other hand, in this embodiment, a cover plate 7, which is shaped as shown in FIG. 7d in the unfolded state, is bent into a U-shape and fitted to the lower end of the arm body 3', which is made of copper. This is configured to be fixed to the arm body 3' with screws 8.

Here, the cover plate 7 is, for example, made of stainless steel plated with chrome and has a rectangular shape.
Moreover, the slits 9, 9 are spaced apart by a predetermined interval.
... are drilled in parallel, and 10 indicates screw holes drilled in the corners.

Therefore, if the cover plate 7 is made into a U-shape and fitted onto the lower end of the arm main body 3', the slits 9, 9...
... and the side and lower surfaces of the arm body 3', a groove substantially equivalent to the terminal groove 6 described above can be easily formed, and 11 in the figure indicates the arm body 3'.
shows an electric heater interpolated into the

Next, the aforementioned terminal straightening device 12 will be explained below with reference to FIG. 3. It consists of a receiving plate 13 and a straightening guide mechanism 14 attached thereto.
Reference numeral 3 denotes a base 13b provided with leg portions 13a, and a receiver 13d fitted flush with the center portion of the upper surface 13c for correction so as to be removable.
The receiver 13d is provided with a receiving recess 13e into which the component body a of the multi-terminal chip component A is partially fitted, as shown in FIG. 3a. A large number of receiving recesses 13e are prepared to suit the dimensions of various multi-terminal chip parts A, and 13f in the figure indicates a push-up rod used to replace the receiver 13d.

The receiving recess 13e is actually a
As shown in the figure, when the component main body a is fitted to this, the terminals c, c, c', c', . It is arranged so that it is in contact with or close to directly above it.

Next, the correction guide mechanism 14 has inner rods 15, 15, . , from this tapered part 15a, the guide hole 5 of the base body 2 in the soldering iron 1,
5..., and the base body 2 is inserted into the raised inner rod 1.
5, 15, etc. as guides, it can freely descend while being held in a horizontal state.

Further, to explain the soldering guide mechanism 16 described above with reference to FIG. 4, in FIG. By fitting the positioning through holes P1, P1... protruding from the printed wiring board P into the tapered parts 16c, 16c formed at the upper ends of these upright guide rods 16b, 16b..., the printed wiring board P can be placed at a predetermined position on the base 16a, and the upright guide rods 16b, 16b, .
can be mated.

Also, in the other embodiment shown in FIG. The base 16 is mounted and fixed at a predetermined position on the base 16a.
A pair of guide fittings 16d, 16d attached to a
extends to a position directly above the printed wiring board P, and connects the upright guide rod 16 from its free end side.
b, 16b, .

In order to carry out the method according to the first invention of the present application by making full use of the various members explained above, first, the component body a of the multi-terminal chip component A is transferred to the receiving plate of the terminal straightening device 12.
3, the terminals c, c..., c', c'... of the above part A are extended onto the correction upper surface 13c by fitting into the receiving recess 13e formed in the receiver 13d. let

Next, a guide hole 5 drilled in the base 2 of the soldering iron 1,
5..., the tapered part 1 of the inner rod 15, 15...
5a, the base body 2 is lowered by the raising inner rods 15, 15..., and at this time, only one or two pairs of heated clamping arms 3, 3... are provided on the soldering iron 1. , one or two pairs of extended terminal groups B1, B1, B2, and B2 are held between them.

That is, by lowering the heating clamping arms 3, 3, . . . and moving them laterally in the direction of the arrow d, as described above, the comb-shaped concave grooves 6, 6, .
, one terminal c, c . . . , c', c' . . . is inserted into each terminal c, c . …, c′,
c'... is pressed against the correcting upper surface of the receiving plate 13 to correct the terminal form of the terminal groups B1, B1, B2, B2.

In other words, vertical deformation of the terminals c, c, . . . , c', c' .

In the illustrated embodiment, the terminal is bent into a crank shape, and a portion of the terminal also comes into contact with the inward side surface 6d of the terminal groove 6, 6....

Next, the transfer suction nozzle tube 4 of the soldering iron 1 is lowered, and its lower end nozzle portion 4a is brought into contact with the upper surface of the component body a of the multi-terminal chip component A, and the transfer suction nozzle tube 4 is moved using a compressor or the like. By setting the suction state, the straightened multi-terminal chip part A is suctioned, and under the suction state, the terminals c, c, c', c' . . .
While maintaining the clamped state, pull up the multi-terminal chip part A, pull out the base body 2 of the soldering iron 1 from the upright inner rods 15, 15, and remove the multi-terminal chip part A as described in detail below. is transferred onto the printed wiring board P.

The above steps and the steps to be described below may all be performed manually, or may be performed automatically by power by configuring an appropriate mechanism.

Now, when the above-mentioned corrected multi-terminal chip component A is to be transferred onto the printed wiring board P, or at an appropriate time before that, the heating clamping arms 3,
3, the electric heater 11 is energized to heat it, so that at least the terminals c, c..., c', c',
c′... will be preheated.

Next, by lowering the transferred soldering iron 1 by the soldering guide mechanism 16, it is placed in a predetermined position on the printed wiring board P, that is, at the multi-terminal chip component mounting location S. The terminals of the multi-terminal chip component A are placed across the preliminary soldering points H' on the plurality of printed circuit PCs attached to the printed wiring board P, and the heating clamping arms 3 are pressed against them. .

Here, since the soldering guide mechanism 16 is equipped with the upright guide rods 16b, 16b as described above, the guide holes 5, 5... in the base 2 of the soldering iron 1 are inserted into these. This allows the multi-terminal chip component A to be accurately placed at the multi-terminal chip component placement location.

At this time, since molten solder H is previously attached to the inner surface 6e of the terminal grooves 6, 6... of the heated clamping arms 3, 3..., the terminals c, c..., c', c', .

If the above solder is melted in this way,
The pressing of the component body a by the transfer suction nozzle pipe 4 remains as it is, and the heating clamping arms 3, 3... are moved to the terminal groups B1, B1, B of the multi-terminal chip component A.
2, after the molten preliminary solder begins to solidify after separating from B2, transfer suction nozzle pipe 4
is raised, and the lower end nozzle portion 4a is inserted into the component body a.
Of course, at this time, suction by the transfer suction nozzle pipe 4 is not performed, and preferably, as described above, the multi-terminal chip part A
It is best to release the suction after the has been placed on the predetermined location on the printed wiring board P, and when pulling up the lower end nozzle part 4a as described above, air should be blown out from the nozzle pipe 4 in the opposite direction. It is also a good idea to air-cool the soldering iron to speed up the solidification.

<<Effects of the Invention>> Since the method according to the first invention of the present application is constituted by the above-described process, there is no need to bond multi-terminal chip components onto a printed wiring board, and the effort for this is unnecessary. Not only this, but the soldering problem associated with the unintentional turning and fixation of components is solved, and the terminal group of multi-terminal chip components can be easily and quickly straightened by a terminal straightening device in advance, and the terminal group can be easily and quickly straightened in advance. Not only can soldering be performed extremely efficiently since the terminals can be preheated, but the soldering iron can be lowered into position effortlessly by the soldering guide mechanism, allowing visual inspection for alignment. There is no need to spend time and effort, or use a computer.

Furthermore, in the present invention, since the heating clamping arms of a unique configuration having grooves for terminals are utilized in the above process, not only straightening but also soldering can have a large thermal effect on the component body of the multi-terminal chip component. By applying this, it is possible to perform soldering without any problems, and it is also possible to improve the accuracy of straightening and soldering.

Furthermore, since the soldering iron of the second invention of the present application also has the appropriate configuration as described above, by utilizing the corresponding terminal straightening device and soldering guide mechanism, it is possible to solder chips with many terminals. Soldering of parts can also be carried out simply, quickly and reliably in the same way as simply soldering chip parts.

[Brief explanation of drawings]

FIG. 1 shows a soldering iron according to the first invention of the present application, in which a and b are a front view and a bottom view of the main parts, respectively, and FIGS. 2 a, b, and c are front views of a known multi-terminal chip component, respectively; A side view, a top view, and FIG. 3A is a partially cutaway front view showing the terminal straightening device in use, FIG. 4B is a front view of the device, and FIGS. 4A and B are views of the soldering guide mechanism Each perspective view showing different types of examples, FIG. 5 is a perspective view of the main part showing the heating clamping arm part in the state of soldering, FIG. 6a is a longitudinal sectional front view of the lower end of the heating clamping arm, FIG. is a vertical side view of the same as above, and FIG. 7 shows another embodiment of the heating clamping arm, in which a, b, and c are respectively a front view, a side view, and a bottom view, and d in the figure is a part of the clamping arm. It is a top view which shows a cover plate. DESCRIPTION OF SYMBOLS 1... Soldering iron, 2... Base body, 3... Heating clamping arm, 4... Transfer clamping nozzle tube, 4a... Lower end nozzle part, 5... Guide hole, 6... Concave groove for terminal, 6
a...Vertical groove, 6b...Horizontal groove, 6c...Downward facing top surface, 6d...Inward facing side, 6e...Back surface, 12...
... Terminal correction device, 13 ... Receiver, 13c ... Upper surface for correction, 13e ... Receiving recess, 14 ... Guide mechanism for correction, 15 ... Inner rod for raising, 16 ... Guide mechanism for soldering, 16a ... Base, 16b ... Standing guide rod, 16d ... Guide metal fitting, A ... Multi-terminal chip component, B1, B2 ... Terminal group, P ... Printed wiring board, PC ... Printed circuit, a ... Part body, c, c'...terminal.

Claims (1)

[Scope of Claims] 1. A multi-terminal chip component in which a required number of pairs of terminals are provided in which a plurality of terminals are extended in parallel outward from the component body is placed in a receiving recess in a receiving plate of a terminal straightening device. The terminal group is arranged on the straightening upper surface of the receiving board by fitting the component bodies, and a separately prepared soldering iron is lowered by the straightening guide mechanism of the terminal straightening device. At the same time, the terminal group is held between the heating holding arms provided with the required number of pairs of soldering irons, and one terminal is inserted into each of the comb-shaped grooves for terminals formed at the lower ends of the holding arms. At the same time, each terminal is pressed against the correcting upper surface of the receiving plate by the inner surface of the terminal groove to correct the terminal form of the terminal group, and the soldering iron can freely draw air. By lowering the transfer suction nozzle pipe at the appropriate time and bringing the lower end nozzle part into contact with the upper surface of the component body, the above-mentioned straightened multi-terminal chip component is suctioned, and under the suction state, the above-mentioned heated clamping arm While holding the terminal in the clamped state, the soldering iron, which is energized and heated at appropriate times, is lowered by the soldering guide mechanism, so that the soldering iron is placed at a predetermined position on the printed wiring board, and is attached to the printed circuit in advance. When the device is placed across multiple preliminary solder points and pressed, and the preliminary solder is melted by heat conduction through the back surface of the holding arm, the pressing of the component body by the transfer suction nozzle pipe continues as it is. In this state, the heated clamping arm is separated from the terminal group of the multi-terminal chip component, and after the molten preliminary solder begins to solidify, the transfer suction nozzle pipe is raised to separate the lower end nozzle from the component body. A method for soldering multi-terminal chip components for surface mounting to a printed wiring board, characterized in that: 2. A patent claim that uses, as a guide mechanism for straightening a terminal straightening device, a plurality of raising inner rods that protrude from a receiving plate and are slidably fitted into guide holes vertically installed in the base of a soldering iron. A method of soldering a multi-terminal chip component for surface mounting according to item 1 to a printed wiring board. 3. As a soldering guide mechanism for the soldering iron, a guide is provided that protrudes from the base on which the printed wiring board is placed so that the printed wiring board is fitted therethrough, and is vertically installed on the base of the soldering iron. A method for soldering a multi-terminal chip component for surface mounting to a printed wiring board as claimed in claim 1, wherein a plurality of upright guide rods are slidably fitted into the holes. 4. As a soldering guide mechanism for the soldering iron, a guide fitting is attached to a base on which a printed wiring board is placed and fixed in a predetermined position and extends above the printed wiring board, and a guide fitting from which the soldering iron is attached. A multi-terminal chip component for surface mounting according to claim 1, which uses a plurality of upright guide rods that are slidably fitted into guide holes provided vertically in the base of the printed wiring board. How to solder to. 5. A transfer suction nozzle pipe that is movable up and down on a base body having a plurality of vertical guide holes, and a pair or more heating clamping arms that are located outside the lower end nozzle part of the transfer suction nozzle pipe and can be opened and closed horizontally. The lower end of the heating clamping arm is formed with a plurality of grooves for terminals in a comb-like shape spaced apart laterally by a predetermined interval, and the grooves for terminals are opened on the inside. The L
A multi-terminal chip component for surface mounting, which is curved in a letter shape, thereby forming a downward facing top surface and an inward facing side surface in the vertical groove and a downward facing back surface in the horizontal groove, is soldered to a printed wiring board. Soldering iron for attaching.