JPH0237492Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a carrier-less automatic soldering device that holds a printed circuit board with a large number of rotating claws and performs soldering.

[Conventional technology]

Printed circuit boards used in electronic devices require a component mounting process in which discrete components are inserted into through-holes or chip components are bonded with adhesive, a soldering process in which these components are soldered to the printed circuit board, and a discrete component mounting process. Electronic components are mounted through various steps such as cutting component leads, incorporating heat-sensitive electronic components using other methods, and inspecting soldered parts.

In the past, each of these processes was independent, and there was no continuous operation between the processes, but from the standpoint of productivity and rationalization, the so-called in-line method, in which each process is connected using a belt conveyor, has been adopted. It's here. In the in-line method, only the printed circuit board must be moved to each process, so the soldering equipment is a carrier-less automatic soldering machine that does not use a carrier.In other words, the printed circuit board is held with a large number of rotating claws, and a fluxer and preheater are used to hold the printed circuit board. A soldering device is used that performs soldering by running over soldering processing equipment such as a soldering bath, a cooling machine, and the like. In addition, the belt conveyor that bridges each process has two belt conveyors that carry both sides of the bottom surface of the printed circuit board so that the leads and chip components of discrete components that protrude from the bottom surface of the printed circuit board do not come into contact with the belt conveyor. A belt conveyor is used.

However, after soldering printed circuit boards with a carrier-less automatic soldering machine, the two-belt conveyor that transports the printed circuit boards to the next process no longer runs smoothly after long periods of use, or the printed circuit boards and belt There have been many accidents in which the conveyor adheres and the printed circuit board is not removed at the place where it should be removed, and the printed circuit board gets caught in the belt conveyor, causing damage to the printed circuit board and the belt conveyor. The cause of this is that sticky flux residue on the bottom of the printed circuit board after soldering transfers from the printed circuit board to the belt conveyor, adheres to the sliding parts and drive parts of the belt conveyor, and prevents the belt conveyor from running smoothly. This is because the printed circuit board may be piled up on the belt conveyor, making it difficult to remove the printed circuit board. Flux residue dissolves in alcohol-based solvents, so it is sufficient to clean the underside of printed circuit boards with a brush containing the solvent after soldering and before transferring them to the belt conveyor. Even if the bottom surface of the belt conveyor is cleaned, flux residue will adhere to the belt conveyor over a long period of time, causing the above-mentioned problems.

[Purpose of invention]

The object of the present invention is to provide a carrier-less automatic soldering device in which no flux residue is transferred to a belt conveyor.

[Structure of the idea]

After the inventor soldered a printed circuit board using a carrier-less automatic soldering device, no matter how carefully he cleaned it with a cleaning device equipped with a solvent or brush, the cause of flux residue adhering to the belt conveyor. Upon investigation, it was discovered that the claws holding the printed circuit board were interfering with cleaning. In other words, the claws hold the printed circuit board by suspending it from below, so the brush does not hit the inside of the part that supports the printed circuit board.
Therefore, the flux residue in this area cannot be completely cleaned.

The present invention is a carrierless automatic soldering device that is equipped with a mechanism that can clean even the parts supported by the claws.The main feature of this device is that it is equipped with a cleaning device that can clean the bottom surface of the printed circuit board on the way out after soldering. At the same time, the carrierless automatic soldering apparatus is provided with a mechanism for intermittently separating the nails from the printed circuit board on the cleaning apparatus.

〔Example〕

The carrier-less automatic soldering equipment includes a fluxer, preheater, solder bath cooler,
A pair of endless chains (2, one not shown) rotates along the frame 1 on these soldering processing equipment.
A large number of claws 3 are attached to the endless chain. The lower ends of the claws are shaped so that the printed circuit board can be supported and suspended from below, and the printed circuit board P is held between the opposing claws while traveling. After the printed circuit board has been soldered, a cleaning device 5 with a brush 4 facing upward is installed below the frame on the outbound path of the vehicle while still holding the printed circuit board with its claws. This cleaning device cleans the bottom surface of the printed circuit board to prevent flux residue from adhering to the belt conveyor when the soldered printed circuit board is transferred to the next process on the belt conveyor. The cleaning device shown in the embodiment has a brush 4 so that when a printed circuit board is placed on a two-belt conveyor, only the portion that comes into contact with the two-belt conveyor, that is, both sides of the lower surface of the printed circuit board, can be cleaned.
are planted in a long and narrow manner in the direction of travel of the printed circuit board. A solvent is supplied to the brush by a solvent supply device (not shown), and the solvent dissolves flux residue and the brush scrubs the bottom surface of the printed circuit board to clean it.

A recess 6 is formed in the frame 1 above the cleaning device 5, and a push cart 7 is installed in front of the recess. Therefore, when the endless chain running along the straight frame reaches the recess, it is pushed by the push cart and enters the recess, causing the chain to curve.

Next, cleaning of the printed circuit board in the carrierless automatic soldering apparatus of the present invention will be explained.

The printed circuit board that has been soldered using a fluxer, preheater, solder bath, cooler, etc. is cleaned by a cleaning device 5 whose lower surface is on the forward path. At this time, since the endless chain 2 moves away from the printed circuit board P along the recessed portion of the frame 1, the claws attached to the endless chain also move away from the printed circuit board. Therefore, while the nail is away from the printed circuit board, the brush 4 cleans the area hidden by the nail. After passing through the recess, the claws come to hold the printed circuit board again. Since all of the claws that hold the printed circuit board pass through these recesses during travel, they are sure to come off the printed circuit board intermittently, and all the parts that were hidden by the claws are cleaned.

[Effect of idea]

When cleaning printed circuit boards, the claws that hold the printed circuit boards come off intermittently from the printed circuit boards, so the parts hidden by the claws can be completely cleaned. It has the excellent effect that flux residue never transfers.

In the embodiment of the present invention, the mechanism for detaching the claws from the printed circuit board is performed using the recessed part of the frame and the push wheel. It goes without saying that structural structures can also be adopted.

[Brief explanation of drawings]

FIG. 1 is a perspective view of the main parts of the present invention, FIG. 2 is a sectional view of the same, and FIG. 3 is a plan view of the same. 1...Frame, 2...Endless chain, 3...
Nail, 4...Brush, 5...Cleaning device, 6...Recessed portion of frame, 7...Push wheel, P...Printed circuit board.

Claims (1)

[Scope of utility model registration request] In a carrier-less automatic soldering machine that holds a printed circuit board with a large number of rotating claws and performs soldering, a cleaning device that can clean the bottom surface of the printed circuit board is installed on the forward path after soldering. is a carrier-less automatic soldering device characterized by being equipped with a mechanism in which the claws are intermittently detached from the printed circuit board.