JP2820260B2 - Jet type soldering equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial application field) The present invention relates to a jet-type soldering apparatus for soldering or plating a printed wiring board or an electronic component. In particular, the suction port of the jet pump is improved.

(Prior Art) FIG. 7 shows a conventional jet-type soldering apparatus provided with a pump suction port above a jet pump, and FIG. 8 shows a conventional jet-type soldering apparatus provided with a pump suction port below the jet pump. It is a soldering device.

In any type of the jet-type soldering apparatus, a jet pump (a kind of centrifugal pump) 2 is provided inside the solder bath main body 1, a nozzle 3 is erected inside the solder bath main body 1, and a motor is provided. Jet pump 2 rotated by 4
Then, the molten solder is pressure-fed to the nozzle 3 and soldering is performed by the molten solder jetted from the nozzle 3.

However, the jet-type soldering apparatus shown in FIG.
A pump suction port 6 is provided in a horizontal partition plate 5 which vertically divides the inside of the solder bath main body 1 into two parts, and the pump 2 sucks molten solder from the pump suction port 6 located on the upper side. In the jet type soldering apparatus, a pump casing 8 communicates with a lower opening of a nozzle 3 via a duct 7, a pump suction port 9 is provided below the pump casing 8, and a pump suction port located below the pump suction port 9. The molten solder is sucked through the opening 9.

Conventionally, in this type of jet-type soldering apparatus, when adjusting the solder wave height of the molten solder jetted from the nozzle 3, the number of revolutions of the motor 4 is variably controlled to adjust the number of revolutions of the jet pump 2, The lift characteristics are adjusted. In this case, only the rotation speed of the jet pump 2 is increased or decreased while the sizes of the pump suction ports 6 and 9 are kept constant.

(Problems to be Solved by the Invention) As described above, since the pump head characteristic (solder wave height) is adjusted by controlling only the pump rotation speed, the rotation speed outside the stable discharge region peculiar to the pump is used. In such a case, there is a drawback that the jet is accompanied by pulsation and surging (a large fluctuation of the jet surface that occurs periodically), and how to obtain a stable jet Was an issue.

The present invention has been made to solve the above-mentioned problem, and an object of the present invention is to change the head resistance of a jet pump by increasing or decreasing the pipe resistance in the vicinity of a pump suction port, thereby improving the pump-specific stability. An object of the present invention is to provide a jet-type soldering apparatus which can operate in a discharge flow rate range and can perform a stable jet without pulsation or surging.

[Configuration of the invention]

(Means for Solving the Problems) The present invention relates to a nozzle provided inside a solder bath main body 11 from a jet pump 14 provided inside the solder bath main body 11.
In a jet-type soldering apparatus in which the molten solder is pressure-fed to the nozzle 18 and soldering is performed by the molten solder jetted from the nozzle 18, the pump suction port 16 opened in the solder bath main body 11 has an opening of the pump suction port 16. A suction area adjuster 31 for variably adjusting the area is provided.

(Operation) The present invention provides a pump suction port 16 by the suction area adjusting body 13.
Optimum head characteristics according to the jet flow form and the like are selected by variably adjusting the opening area.

(Embodiment) Hereinafter, the present invention will be described with reference to the first embodiment shown in FIG. 1 and FIG. 2, the second embodiment shown in FIG. 3 and FIG.
This will be described in detail with reference to FIG. 6, the third embodiment shown in FIG. 6, and the pump characteristic curve shown in FIG.

First, a first embodiment shown in FIGS. 1 and 2 will be described. Solder 13 melted at a constant temperature by a heater 12 is accommodated in a solder bath main body 11, and a jet pump is (The rotating blades of the centrifugal pump) 14 are immersed. The upper part and the lower part of the solder bath main body 11 are divided into two parts by a horizontal partition plate 15, and a round pump suction port 16 corresponding to the jet pump 14 is opened in the horizontal partition plate 15.

The horizontal partition plate 15 is also provided with a square hole 17, and a nozzle 18 is provided upright from the periphery of the square hole 17.

The pump shaft 21 of the jet pump 14 is rotatably held by a bearing portion 22 mounted on the upper portion of the solder bath main body 11, and an electric motor mounted via a mounting plate 33 outside the solder bath main body 11. 24, pulley 25,
The pump shaft 21 is rotationally driven through a rotation transmission mechanism of the belt 26 and the pulley 27.

A suction area adjuster 31 for variably adjusting the opening area of the pump suction port 16 is provided on the upper surface of the horizontal partition plate 15 so as to be able to advance and retreat with respect to the pump suction port 16. The suction area adjusting body 31 is moved and adjusted along a guide 32 provided on the horizontal partition plate 15, as shown in FIG. A U-groove 33 is cut into the suction area adjuster 31 from the pump side, and the U-groove 33 prevents interference between the suction area adjuster 31 and the pump shaft 21.

Then, when the jet pump 14 is rotated by the motor 12, the molten solder 13 in the solder bath main body 11 is
Is sucked into the jet pump 14 via the pump suction port 16 from above, and is sent to the nozzle 18 by centrifugal action by the centrifugal action of the jet pump 14, is jetted from the nozzle 18, and soldering is performed by a part of the jet solder, Mostly solder bath body
The jet pump is returned to the inside of the
Sucked in 14.

In such a circulating system of the molten solder, the opening area of the pump suction port 16 is variably adjusted by the suction area adjusting body 31, so that the fluid resistance at the pump suction port 16 is adjusted to increase or decrease, and optimally adjusted according to the jet flow form and the like. Select a suitable pump lift (solder wave height).

For example, as shown in FIG. 9, even if the pump rotation speed is unchanged, the pump suction port 16
Are small when the opening area of the pump suction port 16 is medium as shown by the curve B, and when the opening area of the pump suction port 16 is large as shown by the curve C. Wave height is different. Also, in the case of the small suction port shown by the curve A, the change in the solder wave height is small with respect to the change in the pump rotation speed, and the jet state is stable, as compared with the case of the large suction port shown by the curve C. Further, in the case of the small suction port indicated by the curve A, since the pump speed is relatively high, the pulsation width of the solder wave height is small.

Next, a second embodiment shown in FIGS. 3 and 4 will be described. The same parts as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

As shown in FIG. 3, a pump casing 42 communicates with a lower opening of the nozzle 18 via a duct 41, and a pump suction port 43 is provided below the pump casing 42. A pump suction port 43 is provided on the lower surface of the pump casing 42.
A suction area adjusting body 44 is provided so as to be able to advance and retreat. As shown in FIG. 4, the suction area adjuster 44 is moved and adjusted along a guide 45 provided on the pump casing 42 to variably adjust the opening area of the pump suction port 43.

Next, a third embodiment shown in FIGS. 5 and 6 will be described. The same parts as in the first and second embodiments are denoted by the same reference numerals, and the description thereof will be omitted.

As shown in FIG. 5 and FIG.
A suction area adjuster 51 in the form of a cap is integrally provided at the center of the lower surface of the pump, and sandwiches the opening area of the pump suction port 43. By changing the cap-shaped suction area adjusting body 51 to one having a large diameter indicated by a two-dot chain line, the opening area of the pump suction port 43 can be further variably adjusted.

The slide-type suction area adjusters 31, 44 can be variably adjusted during operation by providing a mechanism (not shown) that can be operated outside the solder bath body. The area adjuster 51 is selected and mounted at the time of assembling the solder bath.

〔The invention's effect〕

According to the present invention, since the suction area adjusting body for variably adjusting the opening area of the pump suction port faces the pump suction port of the jet pump, even if the jet pump has the same design, the suction area adjusting body can be used. By changing the aptitude of the pump from the large flow economy type to the small flow stable type, it can respond to a wide variety of jet forms, and by adjusting this suction area in conjunction with the adjustment of the pump speed, it is very wide A range of pump characteristics can be selected. In particular, by adjusting the suction area, the jet pump can be used at the optimum rotation speed and the stable jet region can be easily selected, so that a stable jet with little pulsation and surging can be obtained in any jet form, and chip components Is effective in reducing variations in soldering quality.

[Brief description of the drawings]

FIG. 1 is a sectional view of a jet-type soldering apparatus showing a first embodiment of the present invention, FIG. 2 is a top view of a jet-pump part thereof, and FIG. 3 is a jet-type solder showing a second embodiment of the present invention. FIG. 4 is a cross-sectional view of the attaching device, FIG.
FIG. 6 is a sectional view of a jet pump portion showing a third embodiment of the present invention, FIG. 6 is a bottom view of the jet pump portion, FIG. 7 is a sectional view showing an example of a conventional jet type soldering apparatus, The figure is a sectional view showing another example of the conventional jet type soldering apparatus,
FIG. 9 is a graph showing the pump rotation speed-solder wave height characteristic according to the present invention. 11… Solder tank body, 14… Jet pump, 16,43… Pump suction port, 18… Nozzle, 31,44,51 …… Suction area adjustment body.

Claims (1)

(57) [Claims] 1. A jet flow type in which molten solder is pressure-fed from a jet pump provided inside a solder bath main body to a nozzle erected inside the solder bath main body, and soldering is performed by the molten solder jetted from the nozzle. A jet-flow type soldering apparatus, wherein a suction area adjuster for variably adjusting an opening area of the pump suction port faces a pump suction port opened in the solder bath body in the soldering apparatus.