JP3205802B2 - Jet solder bath nozzle - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention belongs to the technical field of a jet solder bath nozzle.

[0002]

BACKGROUND OF THE INVENTION Icicles, bridges, and the like, which are typical phenomena of soldering failure, occur when a printed circuit board separates from a solder surface. In order to prevent this phenomenon, it is generally necessary to appropriately set the relative angle between the printed circuit board surface and the solder flow surface (usually 4 to 7 degrees), and to suppress the relative speed between the printed circuit board and the solder flow. It is valid. In a general solder tank provided with solder guide plates on the entry side and the exit side of the printed circuit board with respect to the solder jet nozzle, the solder flow velocity at the release point at which the printed circuit board separates from the solder is very fast, and this must be controlled. Is also impossible,
There is a problem that icicles easily occur. (For example, Shoko 62
-22295)

As a means for solving such a technical problem, a jet-type soldering apparatus as disclosed in Japanese Patent Publication No. 53-27227 has been proposed. In this apparatus, for example, as shown in FIG. 6, a solder guide plate is provided on the entry side of a solder jet nozzle, and a solder pool (tray) is provided on the entry side.
A dam plate is provided at the upper end of the lower side of the solder pool so as to be vertically adjustable. This device stores the solder jetted from the jet port in the solder pool, and adjusts the solder by the vertical movement of the dam plate. Since the flow velocity on the flow surface is controlled, soldering is performed well, but since the solder surface in the solder pool is set almost horizontal, not only is the transfer angle of the printed circuit board restricted but also However, in order to make the relative speed between the printed circuit board and the solder flow surface zero, there is a problem that the adjustment can be performed only at the speed of the printed circuit board.

In this type of apparatus, it is possible to control the flow velocity of the solder flow surface by adjusting the vertical movement of a solder guide plate provided on the entry side of the substrate and a dam plate provided on the lower side of the solder pool. However, it is almost impossible to adjust the waveform depending on the type of mounted components on the printed circuit board. In the past, a fixed type called a wave homer, or a solder jet nozzle having an angle-adjustable waveform forming plate has been proposed, but not only is the waveform adjustment by such a waveform forming plate limited, There is a difficulty in selecting a point at which the solder separates from the printed circuit board. In addition, there remains an operational problem that the waveform forming plate cannot be operated during the soldering operation.

[0005]

2. Description of the Related Art As a means for solving the technical problems of the invention as described above, a jet-type soldering apparatus as disclosed in Japanese Patent Application Laid-Open No. Hei 5-29339 has been proposed.
This apparatus is a jet-type soldering apparatus in which a printed circuit board is soldered with solder jetted from a solder jet nozzle. In a longitudinal direction of a solder jet portion of the solder jet nozzle, a rod-shaped waveform adjusting means having a cam structure is provided. The rear wave homer is rotatably disposed. According to this apparatus, the above-mentioned problems of the prior art can be solved, and the solder waveform can be arbitrarily selected so as to obtain a solder detachment point adapted to the properties of the printed circuit board. It will be appreciated that a semi-circular recess may need to be formed in the tray component plate for installation of the pivoting rear waveformer, and that the rear waveformer may be recessed in the tray component plate. Since a solder flow gap is formed between them, extra power is required to obtain the effect of solder jetting, and the overall structure is complicated. It should be further noted that the front waveformer and the rear waveformer are approximately the same height, and the cam apex of the rear waveformer may be lower than the upper end of the front waveformer. There is a problem that a large flow in the advance direction changes the flow velocity of the solder, the peelback point of the solder on the printed circuit board changes extremely, and a good soldering effect cannot be obtained.

An electronic component having leads on the upper surface of a printed circuit board is provided, and an electronic component having legs with narrow pitch intervals on the back surface is temporarily fixed with an adhesive, and the two electronic components are jetted into a solder bath. There is a means for soldering at the same time. in this case,
When soldering is performed on an electronic component having a leg portion with a narrow pitch so as not to generate a bridge or the like, the amount of solder attached to the lead is reduced on the electronic component having a lead as shown in FIG. In many cases, solder cracks in the lead portions in the inside occur and are not acceptable as a product. Therefore, there is a need for an improvement in a jet solder tank nozzle that can sufficiently secure the amount of solder attached to the lead.

SUMMARY OF THE INVENTION An object of the present invention is to provide a peelback point suitable for an electronic component having leads and an electronic component having legs with a narrow pitch interval. The object of the present invention is to provide a high flow solder bath nozzle having a high fillet of solder.

[0008]

Means for Solving the Problems The object of the present invention is to provide a
At the top of the front nozzle configuration plate that constitutes the flow nozzle,
Draw an arc toward the approach direction of the printed circuit boardWaveForming plate
(Front wave homer)Out the solder one
OnePreform the upper part of the nozzle configuration plate at the rear of the jet nozzle.
Inclined toward the approach direction of the printed circuit board, and the upper end is
Corrugated plate with approximately the same height as the front wave homer (rear
Wave homer), and this rear wave homer
Of the printed circuit board in the direction of the printed circuit board
The upper part is inclined and the upper part is the front and rear waveformers.
Tall from the topIn order to prevent solder leakage,
AttachedWeir plate (damper)Up and downLet's arrange this
Between the damper and the rear wave homer
The direction of advance of the printed circuit board due to the solder pool of the laser structure
Form a static zone of jet solder that does not allow solder to flow out,
Adhesive on the back side of the printed circuit board on the upper side of this stationary zone
Detachment point of electronic components temporarily fixed at (Peel back point
), The electronic part arranged on the lower surface of the printed circuit board
Separation point (peel back point) of product lead
Set, fillet thick, bridge and icicle phenomenon
By enabling soldering that does not generate
Achieved. The above purpose is the inner surface of the rear nozzle plate
Below, an auxiliary wave home parallel to the rear wave homer
The auxiliary wave homer is attached
By increasing the static zone width of solder
Achieved.

[0009]

Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a vertical front view of a jet nozzle, FIG. 2 is a vertical front view of a jet nozzle of another embodiment, FIG. 3 is an enlarged front view of a main part showing a peel back point of different electronic components, and FIG. FIG. 5 is an enlarged cross-sectional view illustrating a soldered portion of a lead according to the first embodiment.

The embodiment of FIG. 1 will be described in detail. A
Is a solder jet nozzle mounted in a solder bath (not shown). The jet nozzle A is configured as follows.

The front nozzle constituting plate 1 constituting the solder jet nozzle A is inclined toward the direction of entry of the printed circuit board 2, and is positioned above the nozzle constituting plate 1 in the direction of entry of the printed circuit board 2. A front waveformer 4 for drawing out the solder 3 in a circular arc is formed. The front waveformer 4 is formed separately from the nozzle component plate 1 so that the front waveformer 4 can be adjusted vertically with respect to the nozzle component plate 1.
In some cases, the configuration may be such that the solder waveform is arbitrarily adjusted.

At least the upper half of the rear nozzle forming plate 5 constituting the jet nozzle A is formed parallel to the inclination with the front nozzle forming plate 1, and the rear nozzle forming plate 5 is formed.
Is further inclined toward the direction in which the printed circuit board 2 enters, and a rear wave former 6 having an upper end substantially at the same height as the front wave former 4 is provided. 7 is formed.

The printed circuit board 2 of the rear wave homer 6
A damper 8 whose upper end is inclined higher than the upper ends of the front and rear wave formers 4 and 6 so as to be vertically movable. The solder pool 9 having a tray structure formed between the damper 8 and the rear wave homer 6 forms a static zone a of the jet solder in which the solder does not flow out in the direction in which the printed circuit board 2 advances. At the upper end of the damper 8, a suppression plate 8a for preventing the outflow of the solder 3 along the advance direction of the printed circuit board 2 is provided so that a stationary zone a of the solder can be established. In the figure, reference numeral 10 denotes a fastening bolt provided on the rear nozzle constituting plate 5, reference numeral 11 denotes a vertically long guide hole provided below the damper 8, and reference numeral 12 denotes a rectifying plate for solder. The jet nozzle A is configured as described above.

An auxiliary wave former 13 parallel to the rear wave former 4 is provided below the inner surface of the rear nozzle forming plate 5 so as to be fastened by a virtual line. The width of a can be increased.

In the embodiment shown in FIG. 2, the upper half of the rear nozzle constituting plate 5 constituting the jet nozzle A is vertical.
The rest is the same as the configuration shown in FIG.

[0016]

[Description of Operation] The operation of the present invention will be described with reference to FIG. The flow of the molten solder that is pressure-fed in the jet duct is adjusted by the current plate 12 of the jet nozzle A, and is jetted from the jet port 7. At this time, since the front and rear nozzle component plates 1 and 5 are inclined toward the direction of entry of the printed circuit board 2, the flow of the solder 3 jetted from the jet port 7 is such that the flow of the solder 3 is opposed to the direction of entry of the printed circuit board 2. Becomes mainstream. On the other hand, a part of the solder jetted from the jet port 7 passes through the upper part of the rear wave former 6 and is stored in the solder pool 9.
The flow of the solder inside is offset by the effect of flowing in the direction of entry of the printed circuit board 2 and the effect of entering the flow indicated by the arrow. a is formed, while
A raised portion is naturally formed at the upper end of the damper 8 due to the surface tension of the solder, and the solder does not flow out in the direction in which the printed board 2 advances. Further, the solder that is going to flow out is prevented by the suppression plate 8a. When the printed circuit board 2 is soldered in such a state, as shown in FIG. 3, the peel-back point of the electronic component 15 temporarily fixed to the back surface of the printed circuit board 2 by the adhesive 14 becomes the static zone a of the jet solder. Is set on the upper side, and the legs 16 of the electronic component 15 at a narrow pitch are soldered with a solder amount suitable for soldering, so that there is no bridge. The relatively long lead 19 of the electronic component 18 mounted on the upper surface of the printed circuit board 2 has a peel back point set on the lower side of the stationary zone a of the jet solder. Irrespective of this, soldering with a sufficient amount of solder suitable for soldering the leads 19 is performed, and the conventional accident such as solder cracking due to insufficient amount of solder can be rationally prevented. Next, Table 1 shows comparison data of the amount of solder adhesion.

[Table 1]

[0017]

According to the configuration of the present invention as described above,
The following effects can be obtained. (A) In the first embodiment, the front and rear wave formers and the tall damper obstruct the flow zone of the solder flowing toward the printed circuit board in the direction of the printed circuit board.
Stop, and a static zone of the jet solder can be formed on the advance side of the printed circuit board, and a peel back point can be set on the upper side and lower side of the static zone of the jet solder, respectively. By soldering suitable electronic components, there is no excess or deficiency in the amount of solder attached, soldering can be performed rationally without accidents such as solder cracking, and the soldering efficiency can be improved. (B) According to the second aspect only, by providing the auxiliary wave homer, the width of the stationary zone of the jet solder where the peel back point can be set can be increased, and the soldering efficiency can be improved. The formation of (c) suppression plate, along with outflow of the solder of the printed circuit board advancing direction can be further prevented, establishes a quiescent zone of the jet solder attained is further improved soldering efficiency.

[Brief description of the drawings]

FIG. 1 is a vertical sectional front view of a jet nozzle.

FIG. 2 is a vertical sectional front view of a jet nozzle according to another embodiment.

FIG. 3 is an enlarged front view of a main part showing peelback points of different electronic components.

FIG. 4 is an enlarged sectional view showing a soldered portion of a lead according to the present invention.

FIG. 5 is an enlarged sectional view showing a soldered portion of a lead according to a conventional technique.

FIG. 6 is a vertical sectional front view of a conventional jet nozzle.

[Explanation of symbols]

 Reference Signs List A Jet nozzle 1 Nozzle component plate 2 Printed circuit board 3 Solder 4 Front wave homer 5 Nozzle component plate 5a Inclined portion 6 Rear wave homer 7 Jet port 8 Weir plate (damper) 8a Suppression plate 9 Solder pool 10 Tightening bolt 11 Guide slot DESCRIPTION OF SYMBOLS 12 Rectifier plate 13 Auxiliary wave homer 14 Adhesive 15 Electronic component 16 Leg 18 Electronic component 19 Lead a Stationary zone

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-51-43345 (JP, A) JP-A-60-74842 (JP, U) JP-A-58-195469 (JP, U) 1563 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) H05K 3/34

Claims (2)

(57) [Claims] 1. A front nozzle constituting a solder jet nozzle.
On the top of the component board in the direction
Draw an arcWasSet the wave forming plate (front wave homer)
KeOut the solder on the other hand, The upper part of the nozzle structure plate that constitutes the jet nozzle
Slant toward the entry direction of the printed circuit board, and
A corrugated plate substantially flush with the front waveformer
(Rear wave homer).
Of the printed circuit board on the side of the armor's printed circuit board
The upper part is inclined along the direction, and the upper part is the front and rear waves.
Taller than top edge of homerAnd also to prevent solder from flowing out
Suppression plate attachedWeir plate (damper)Up and downArrange
Shimeme, between this damper and rear wave homer
Of the printed circuit board
A static zone of the jet solder that does not allow the solder to flow out in the advance direction
Forming  Adhesive on the back side of the printed circuit board on the upper side of this stationary zone
Detachment point of electronic components temporarily fixed at (Peel back point
), The electronic part arranged on the lower surface of the printed circuit board
Separation point (peel back point) of product lead
Set, fillet thick, bridge and icicle phenomenon
The feature is that soldering that does not cause cracking can be done.
And the jet solder tank nozzle. 2. An auxiliary wave homer parallel to the rear wave homer is provided below the inner side surface of the rear nozzle forming plate, and the auxiliary wave homer increases the static zone width of the jet solder. The jet solder tank nozzle according to claim 1, wherein