JPS6116925Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a heating device for an automatic soldering machine for soldering printed circuit boards.

Printed circuit boards are soldered by sequentially passing through a fluxer, a heating device, a soldering bath, a cooler, a lead cutter, etc. installed in an automatic soldering device. The heating device in automatic soldering equipment dries the liquid flux applied with fluxer and activates it to facilitate soldering.It also prevents printed circuit boards from being thermally damaged when immersed in high-temperature molten solder. It should be preheated to prevent this.

Conventional heating devices include a meandering sheathed heater, a panel heater that generates heat from a flat surface, or a combination of a sheathed heater and a panel heater. However, conventional heating devices have the drawback that flux adheres to the surface during long-term use, and this carbonizes, reducing thermal efficiency and corroding the surface. This is because the flux applied to the printed circuit board falls onto the heating device. In other words, the heating device dries the solvent in the flux, but with conventional heating devices, heating and drying is performed only after the heating device is directly above the heating device, so the solvent does not fly away immediately and the flux falls onto the heating device. It's something you end up doing.

There is a heating device that blows out hot air in front of a heating element (Utility Model Publication No. 50738/1983), but this heating device has a hot air generation case that is equipped with a heating element and a blower separately from the heating element, so the shape is different. This resulted in a large size and limited the number of installation locations. In addition, in order to expect a synergistic effect between the hot air and the heating element, the heating device has a hot air outlet facing toward the upper heating element, and therefore, the printed circuit board is heated only when it is placed on the heating device. . Therefore, the solvent in the flux applied to the printed circuit board does not volatilize even on the hot air generating casing and falls onto the hot air generating casing and the upper heating element, causing the above-mentioned problems.

The object of the present invention is to provide a heating device that has a simple structure despite blowing hot air, can be compact in shape, does not limit the installation locations, and does not cause flux to drip onto the heating device. . The present invention will be explained below based on the drawings.

A plurality of heaters 2 and 2' are installed in the rectangular frame 1 horizontally with respect to the printed circuit board advancing direction, and the lower part of the heater 2' installed on the side where the printed circuit board P enters is A blower 3 is installed. The blower 3 is oriented obliquely upward, opposite to the direction in which the printed circuit board P enters (arrow A), and blows air through the heater 2'. One end of the upper part of the blower is rotatably supported so that the blowing direction can be changed, and the other end slides in an opening drilled along a rotational track and is attached to a thumbscrew at an appropriate inclined position. 4
It can be fixed by

The heater used in this invention is suitable for mid-infrared rays, which allows delicate temperature adjustment, but for mid-infrared rays, it is best to use gold plating at the bottom of a heat-resistant glass tube and install a spiral mid-infrared heater on top of it. It has good thermal efficiency and can have a long life.

Here, the heating state of the heating device of the present invention having the above structure will be explained.

When the heaters 2 and 2' are energized to heat them and the blower 3 is operated, the air sent by the blower passes through the heater 2' installed on the side where the printed circuit board enters. This is where the wind gets heated. Then, when the printed circuit board is moved in the direction of arrow A by a transport device (not shown),
First, in front of the heating device, the hot air is heated by the heater 2' and blown upward obliquely. Here, the solvent in the flux is evaporated by the hot air, and excess flux is blown away backward. Therefore, when the printed circuit board advances further and comes directly above the heating device, the flux has become uniformly thin and has almost been volatilized by the solvent. The printed circuit board is then heated to a temperature suitable for soldering by a plurality of heaters 2 on the heating device.

In the present invention, a plurality of heaters are installed laterally in the direction in which the printed circuit board advances, so if a voltage regulator is installed on each heater, the temperature of each heater can be controlled in any way. Therefore, even if the size, thickness, etc. of the printed circuit board to be soldered changes, an appropriate temperature distribution can be obtained.

As explained above, since the heating device of the present invention can be made compact in shape, it is not limited to the location where it can be installed. This has excellent effects that have not been seen in the past.

[Brief explanation of the drawing]

FIG. 1 is a plan view of an embodiment of the present invention, and FIG. 2 is a front view thereof. 2, 2'...Heater, 3...Blower, P...
Printed board.

Claims (1)

[Scope of utility model registration request] In addition to installing multiple heaters laterally in the direction in which the printed circuit board advances, an air blower that blows air in the opposite direction of the printed circuit board through the heater is installed at the bottom of the heater installed on the printed circuit board entry side in a variable blowing direction. A heating device for automatic soldering equipment featuring: