JP2002118354A - Soldering device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a soldering device with which manual correcting operation in a preheat part is unnecessitated and further, stable temperature control is enabled. SOLUTION: A preheat part 13 is provided with a heater 13a, a radiation plate 13c surrounding the heater 13a, and a temperature sensor 21 for detecting the temperature of the preheat part 13. The temperature sensor 21 is located to detect a temperature on the surface of the radiation plate 13c opposing to a conveyance plane 10 of a printed circuit board P, the power of electrification to the heater 13a is controlled by a power control unit 20 so that a temperature TS detected by the temperature sensor can get close to a target temperature setting value TR, and the printed circuit board P is preheated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a soldering apparatus for supplying a printed circuit board preheated in a preheating section to a solder tank and soldering the same to the printed circuit board.

[0002]

2. Description of the Related Art FIG. 3 shows a soldering apparatus for preheating a printed circuit board P on which a surface mount component and an insert component (a component having leads) are mounted in a preheating section 13 and passing the solder through a solder bath 5. Show.

During the soldering operation, the work environment should not be contaminated by the heat generated from the solder bath 5 or the flux applied to the soldering surface of the printed circuit board P by the gas generated by touching the molten solder J. , The solder bath 5 is surrounded by a housing 14. The housing 14 has a carry-in port 16a and a carry-out port 16b for the printed circuit board P, and the printed circuit board P carried into the housing 14 from the carry-in port 16a is carried along the board carrying direction [the direction of the arrow A]. Is done.

[0004] As shown in FIGS. 4 and 5,
Good melting solder J for printed circuit board P on which components are mounted
And a secondary jet nozzle 2 for removing excess molten solder J from the printed circuit board P to which solder has been supplied. A primary nozzle duct 3 is connected to the primary jet nozzle 1, a secondary nozzle duct 4 is connected to the secondary jet nozzle 2, and these ducts 3, 4 are solder baths 5 in which molten solder J is stored. Is soaked inside. Then, by rotating and driving the jet impellers 6 and 7 arranged so as to face the openings at one ends of the ducts 3 and 4, the molten solder J is transferred from the primary jet nozzle 1 and the secondary jet nozzle 2 to the transfer surface 10. It is configured to squirt toward. At the upper end of the primary jet nozzle 1, a solder wave forming plate 9 having a large number of jet ports 8 opened is attached.

When the printed circuit board P is supplied to the solder bath 5, the printed circuit board P is preheated by a preheating unit 13 provided below the transfer surface 10 in order to activate the flux and reduce the heat shock of the board. You. 13b is a cover made of a heat insulating material.

The preheated printed circuit board P is sent to the solder bath 5 so that the surface on which the land is formed contacts the molten solder J, and the molten solder J ejected when passing through the solder bath 5 is applied to the land by an appropriate amount. The solder is adhered and soldered. Gases generated during the soldering operation are forcibly exhausted from the duct 15. Reference numeral 12 denotes a curtain provided at the carry-out port 16b, which is formed of a flexible material such as rubber so as to allow the printed circuit board P to pass therethrough and to prevent air from flowing.

The printed circuit board P that has passed through the solder bath 5 passes through the outlet 16b and the curtain 12 and passes through the housing 1
The substrate is transported to the outside of the substrate 4 and further transported to a subsequent stage by the transport means, and is transported to a cooling zone (not shown) to prevent the substrate from warping.

FIG. 6 shows the details of the preheating section 13 of the soldering apparatus configured as described above. The heater 13a
A heater body 13d made of a heating wire, a metal radiation plate 13c surrounding the heater body 13d, the heater body 13d and the radiation plate 13
c and a filling material filled between them. The radiation plate 13c is provided to make the temperature of the radiation surface facing the transfer surface 10 of the printed circuit board P uniform, and when power is supplied to the heater body 13d, the radiation plate 13c is heated, and the radiation plate 13c is heated. The printed circuit board P is preheated by the radiation heat 13c.

[0009] Inside the heater 13a, the heat-sensitive portion 21a of the temperature sensor 21 consisting of a thermocouple is inserted to the vicinity of the center, so that the detected temperature T _S of the temperature sensor 21 detects approaches the target temperature setting value T _R, the power The control unit 20 controls the heater 13
a is controlled.

[0010]

In the conventional pre-heater unit 13 [0007], as the detected temperature T _S of the temperature sensor 21 which detects the temperature of the heater body 13d itself, approach the target setting temperature T _R, the power control also part 20 is operated by setting the preheating temperature of interest as a target set temperature T _R for controlling the energization of the heater 13a, the printed board P
Cannot be preheated to the preheat temperature intended for Therefore, it is necessary to manually modify the operation of the target setting temperature T _R while driving.

In order to preheat the printed circuit board P to the preheating temperature without performing such a manual operation,
As shown in FIG. 7, there is a configuration in which the temperature sensing part 21 a of the temperature sensor 21 is arranged in a space between the transfer surface 10 of the printed circuit board P and the radiation plate 13 c to measure the temperature.
Since the temperature depends on the flow of air in the housing 14, stable temperature control cannot be performed.

It is an object of the present invention to solve the above-mentioned problems and to provide a soldering apparatus which does not require a manual correction operation in a preheating section and can perform stable temperature control.

[0013]

The soldering apparatus according to the present invention is characterized in that the temperature sensor of the preheating portion is arranged to detect the surface temperature of the radiation plate on the side facing the transfer surface of the printed circuit board. .

According to this invention, by controlling the temperature of the surface close to the printed circuit board, it is easy to preheat the printed circuit board to the preheat temperature intended for the printed circuit board, and to realize stable temperature control without being influenced by the air flow. it can.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A soldering apparatus according to the present invention is a soldering apparatus for supplying a preheated printed circuit board through a preheating section to a solder tank and soldering the printed circuit board to the printed circuit board. A heater for heating the printed circuit board, a radiating plate surrounding the heater, and a temperature sensor for detecting the temperature of the preheating portion, and energizing the heater so that the detected temperature of the temperature sensor approaches a target temperature set value. Is controlled by the power control unit,
The temperature sensor may be arranged to detect a temperature of a surface of the radiation plate on a side facing a transfer surface of the printed circuit board.

FIG. 1 shows a specific embodiment of the present invention.
This will be described with reference to FIG. In addition, FIG.
7 are denoted by the same reference numerals and described.

In this embodiment, the temperature sensor 21 is
It differs from the above-mentioned conventional example in that it is arranged to detect the temperature of the surface of the radiation plate 13c. As shown in FIGS. 1 and 2, the configurations of the heater 13 a and the sensor 21 themselves are the same as those in FIG. 6, but the heat-sensitive portion 21 a of the sensor 21 is fixed to the center of the surface of the radiation plate 13 c at the welding location 22. I have.

When power is supplied to the heater body 13d,
Temperature sensor 21 detects the surface temperature of the radiation plate 13c, the detected temperature T _S is to approach the target temperature set value T _R, energization of the heater 13a by the power control unit 20 is controlled.

[0019] With this configuration, it becomes easy to set the preheating temperature for the purpose of more printed board P than conventional operation to be manually corrected operating the target setting temperature T _R with a cumbersome manual operation Is no longer needed. In addition, since the temperature of the radiating plate 13c is directly measured instead of measuring the temperature of the atmosphere heated by the radiating plate 13c, the temperature is not affected by the flow of air in the housing 14, and a stable temperature is obtained. Control can be performed.

As described above, in the soldering apparatus according to this embodiment, the preheated section 13 controls the temperature stably and supplies the preheated printed circuit board to the solder tank 5, so that good soldering is realized. it can.

In the above description, the heat sensitive portion 21a of the heater 21 is fixed to the radiation plate 13c by welding. However, the present invention is not limited to this.
Alternatively, the temperature may be simply detected by bringing the plate 1a into contact with the radiation plate 13c.

[0022]

As described above, according to the soldering apparatus of the present invention, a heater for heating a printed circuit board, a radiation plate surrounding the heater, and a temperature sensor for detecting the temperature of the preheat section are provided in the preheating section. The power control unit controls the power supply to the heater so that the temperature detected by the temperature sensor approaches the target temperature set value, and the temperature sensor faces the transfer surface of the printed board of the radiation plate. By arranging to detect the temperature of the side surface,
Preheating of the printed circuit board can be performed accurately, and good soldering can be performed.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view of a soldering apparatus according to an embodiment of the present invention.

FIG. 2 is a plan view of a pre-heater unit of FIG.

FIG. 3 is a schematic sectional view of a conventional soldering device.

FIG. 4 is a schematic overall perspective view of the solder bath of FIG. 3;

FIG. 5 is a schematic front sectional view of the solder bath of FIG. 3;

FIG. 6 is a plan view of a pre-heater unit in FIG. 3;

FIG. 7 is a schematic cross-sectional view of a soldering apparatus showing another example different from FIG.

[Explanation of symbols]

5 Solder tank 10 Transfer surface 13 Preheat section 13a Heater 13c Radiant plate 20 Power control section 21 Temperature sensor 21a Heat sensitive section A Board transfer direction P Printed circuit board T _S detection temperature T _R target temperature set value

Continuation of the front page (72) Inventor Kenichi Nakajima 1006 Kazuma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. F term (reference) 4E080 AA01 AB03 AB05 5E319 AC01 BB01 CC24 CC58 CD31 CD51 GG03

Claims (1)

[Claims] 1. A soldering apparatus for feeding a pre-heated printed circuit board through a pre-heating section to a pre-heated printed circuit board for soldering to the printed circuit board, wherein the pre-heating section includes a heater for heating the printed circuit board; A radiating plate surrounding the heater and a temperature sensor for detecting the temperature of the preheating unit are provided, and the power supply to the heater is controlled by a power control unit such that the temperature detected by the temperature sensor approaches a target temperature set value. A soldering device in which the temperature sensor is arranged to detect a temperature of a surface of the radiation plate on a side of the radiation plate facing a transfer surface of the printed circuit board;