JPH0244930Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an automatic soldering device that automatically solders small printed circuit boards in a static flow soldering bath.

[Prior art]

Conventionally, when soldering the patterned surface of a small printed circuit board, the general practice was to hold the printed circuit board manually with a soldering iron or with tweezers and immerse it in a static flow solder bath. There is.
However, when it is done manually using a soldering iron, it is time-consuming and costly, and also when using a soldering bath, it is basically done manually, especially when it comes to the soldering bath. The immersion time varies, and when taking out the printed circuit board from the solder tank, the printed board must be moved in the direction of solder flow in the solder tank and taken out at an angle, which requires skill, which may cause solder bridges or solder horns. The problem was that there were many soldering defects, the quality was unstable, and the work was generally troublesome.

[Purpose of invention]

The present invention was developed in view of the above circumstances, and its purpose is to automatically spray flux onto the patterned surface of a printed circuit board and solder it using a static flow soldering bath, with almost no manual work required. To provide an automatic soldering device that can automatically perform soldering with stable quality.

[Summary of the idea]

In this invention, a pallet with a printed circuit board mounted thereon is transferred to a flux application station by a first transfer device, flux is applied to the pattern surface by spraying, and then the pallet is transferred to the upper part of a static flow soldering bath by the first transfer device. Then, the lifting mechanism lowers the pallet while tilting it so that the upstream side of the static flow solder tank is at the bottom, and dips the patterned surface of the printed circuit board into the static flow solder tank. The pallet is tilted once so that the downstream side is on top, and then lifted up by the lifting device, and the soldered printed circuit board is placed on the second pallet together with the pallet.
The present invention is characterized in that the transfer device transfers the printed circuit board from above the static flow solder bath to the take-out position, and all operations other than attaching and detaching the printed circuit board to and from the pallet are automatically performed.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. Reference numeral 1 denotes a machine frame of an automatic soldering apparatus, and a guide rail 3 for guiding a pallet 2, which will be described later, is installed substantially horizontally on the right half of the machine frame. Reference numeral 4 denotes a transport escapement as a first transport device which is supported so as to be horizontally movable and rotatable approximately parallel to the guide rail 3. A cylinder 5 for left and right movement is connected to the left end of this. is provided with a motor (not shown) for rotating the transport escapement 4. A plurality of transport arms 6 are attached to this transport escapement at a constant pitch. 7 is a flux application station installed approximately in the middle of the guide rail 3;
To explain this in detail, reference numeral 8 denotes a cylindrical shield case which is vertically movably disposed below the guide rail 3 and is open at both upper and lower ends, and a receiver 9 is provided below this. 10 is a solvent tank, and 11 is a flux tank. Sending pipes 10a and 11a from these are joined at a joint 12, and the tip of a spray pipe 13 whose one end is connected to this joint 12 is introduced into the shield case 8. A spray nozzle 14 is installed at the tip of the spray pipe 13.
is attached. Reference numeral 15 denotes a lifting device provided near the left end of the guide rail 3. To explain this in detail, 16 and 17 are first and second cylinders, and a guide body 18 is attached to the tip of the rod 16a of the first cylinder 16. The rod 17a of the second cylinder 17 is supported so as to be horizontally movable left and right.
A guide body 19 is fixed to the tip. Reference numeral 20 denotes a receiving member whose left and right ends are rotatably connected to guide bodies 18 and 19, respectively. The guide rail 3 is arranged to extend substantially horizontally to the left end of the guide rail 3. 21 is located directly below the receiving member 20 and is attached to the machine frame 1.
The molten solder 22 on the surface of the static flow solder tank is provided inside the tank so as to be movable up and down, and the melted solder 22 flows gently in the direction of the arrow A to the inner peripheral wall 21a of the solder tank 21.
Therefore, the solder 22 on the surface of the solder tank 21 is always kept free of oxide film. Reference numeral 23 denotes a belt conveyor serving as a second transfer device provided in the machine frame 1 from the left end of the guide body 18 toward the left, and its left end reaches a take-out position B outside the machine frame 1. Reference numeral 24 denotes a chain conveyor for returning the pallet 2 from the take-out position B side to the right.
0 and the guide rail 3 so as to be substantially parallel to them.

On the other hand, the pallet 2 will be explained with reference to FIG. 4. It is made of a heat-resistant non-metallic material and has a substantially flat plate shape, and has a concave portion serving as a device portion into which a printed circuit board 25 to be soldered is inserted. For example, two 2a are formed. A through hole 2b corresponding to a soldering location on the printed circuit board 5 is bored in the bottom surface of the recess 2a.

Next, the operation of the above configuration will be explained. first,
The pallet 2 with the printed circuit board 25 mounted in the recess 2a is placed on the right end of the guide rail 3, for example, by hand. In this state, at a predetermined timing, the conveyance escapement 4 is rotated in the direction of arrow C with the cylinder 5 extended, and one of the conveyor arms 6 is positioned slightly to the right of the right end of the pallet 2, and then Cylinder 5 is deflated. Then, the pallet 2 is transferred to the left by the conveying arm 6 by a distance corresponding to the arrangement pitch of the conveying arm 6, and after being transferred, the conveying escapement 4 is rotated back in the opposite direction of arrow C, and the conveying arm 6 is moved to the left. The pallet 2 is removed from the right end of the pallet 2, and then the cylinder 5 is extended again, and the above-mentioned operation is repeated at a predetermined timing, so that the pallet 2 is repeatedly transferred on the guide rail 3 by a distance corresponding to a pitch. Now, when one pallet 2 is transferred directly above the flux application station 7 and stopped, the shield case 8 is immediately moved upward and its upper end approaches the lower surface of the pallet 2 (see Fig. 1).
Then, from the spray nozzle 14, a mixture of solvent and flux from the solvent tank 10 and the flux tank 11 is atomized and applied to the patterned surface of the printed circuit board 25 through the through hole 2b. . During this process, the excess liquid flows down the inner surface of the shield case 8 and flows down into the receiver 9.
can be stored in When the coating on the pattern surface is completed as described above, the shield case 8 is lowered to its original position (see FIG. 2).

Then, at the flux application station 7, the printed circuit board 25, whose patterned surface has been coated with solvent and flux, is intermittently transferred leftward by the transport arm 6, as described above, to the receiving member 20. When the pallet 2 is transferred upward, the rod 16a of the first cylinder 16 contracts and the pallet 2
is tilted downward to the left (see Figure 2).
At this time, the pattern surface of the printed circuit board 25 is in a state separated from the surface of the solder 2 in the static flow solder tank 1. When the rod 16a of the first cylinder 16 contracts, then the rod 17a of the second cylinder 17
contracts slowly. Then, the inclination of the receiving member 20 gradually becomes gentler, the receiving member 20 rotates in the direction of arrow D, and the guide body 18 horizontally moves leftward [opposite of arrow A].
direction), and the printed circuit board 25
The pattern surface gradually moves from left to right in the static flow soldering bath 21.
(See FIG. 3). When the patterned surface of the printed circuit board 25 comes into contact with the solder 22, the resist made of solvent and flux applied to the surface is heated to a high temperature and generates a large amount of gas. Since the board 25 rotates gently and gradually changes from an inclined state to a horizontal state with respect to the surface of the solder 22, the generated gas is released along the inclined surface of the printed board, and at the same time, the printed board Since the opening direction of the slope is set along the flow direction of the solder, the flow of the solder promotes the flow of gas, so that the gas escapes well to the side and the gap between the pattern surface and the surface of the solder 22 is It is reliably prevented from causing solder failure due to gas getting involved. In this way, when the air cylinder 17 contracts, the receiving member 20 and the pallet 2 become approximately horizontal, and the pattern surface of the printed circuit board 25) becomes immersed in the solder 22 of the solder bath 21. For example, it is stopped for about 3 seconds. Then, after 3 seconds have elapsed, the rod 17a of the second cylinder 17 is gently extended first. Then, contrary to the above, the receiving member 20 and the pallet 2 are rotated in the opposite direction of the arrow D and moved to the right (in the direction of the arrow A), and the solder is removed while moving along the flow of the solder 22. 22, the right end of the printed circuit board 25 is gradually raised (see FIG. 5), and eventually the right end of the printed circuit board 25 is also separated from the solder 22, and then the rod 16a of the first cylinder 16 is extended. Then, the guide bodies 18, 19 and the receiving member 20 are returned to a horizontal state on the same level as the guide rail 3. Then, when the cylinder 5 contracts, the pallet 2 that has finished soldering and is located on the receiving member 20 is transferred from above the receiving member 20 to the belt conveyor 23 by the conveying arm 6, It is transferred to the take-out position B by the belt conveyor 23. When the soldered printed circuit board 25 is manually removed from the pallet 2 that has reached the take-out position B and the empty pallet 2 is placed on the chain conveyor 25, the pallet 2 is transferred to the right and guided. Since it is returned to the vicinity of the right end of the rail 3, the above-described operation is repeated to solder the printed circuit board 25.

According to the above configuration, the work is very simple because no human effort is required except for attaching and detaching the printed circuit board 25 to and from the pallet 2. In addition, since the solvent and flux applied to the printed circuit board 25 are stored in a tank, the solvent evaporates and the specific gravity decreases, unlike the conventional method in which the solvent is stored in a container with an open top to dip the printed circuit board. Since it does not change, there is no need to manage specific gravity, making work even easier.

Further, in the above configuration, when taking out the printed circuit board 25 immersed in the static flow solder bath 21, the right end of the printed circuit board 25 located on the downstream side of the solder flow is raised almost directly upward by the second cylinder 17, As a result, the left end of the printed circuit board 25 is guided by the horizontal movement of the guide body 18 so that the left end of the printed circuit board 25 moves horizontally to the downstream side of the solder flow in the solder bath 21 and is separated upward from the surface of the solder 22. The occurrence of soldering defects such as bridges and solder horns is prevented as much as possible, and quality becomes stable. If a plurality of recesses 2a of different shapes are provided in one pallet 2, different types of printed circuit boards 25 can be soldered at the same time. Furthermore, it goes without saying that the attachment and detachment of the printed circuit board 25 to and from the pallet 2 can be done mechanized by a robot or the like instead of manually.

[Effect of idea]

As is clear from the above description, the present invention uses a first transfer device to transfer a pallet with printed circuit boards to a flux coating station, coats the patterned surface with flux, and then uses the first transfer device to statically apply the flux. The pallet is transferred to the upper part of the static flow soldering tank, and the pallet is lowered by a lifting device while tilting the pallet so that the upstream side of the static flow soldering tank is at the bottom, so that the patterned surface of the printed circuit board is dipped into the static current soldering tank. After that, the pallet is once tilted so that the downstream side of the static flow soldering tank is at the top, and the lifting device lifts the pallet, and the soldered printed circuit board is transferred together with the pallet from above the static current soldering tank by a second transfer device. Since it is transferred to the take-out position, the spraying of flux on the patterned surface of the printed circuit board and the soldering using the static flow soldering bath are automatically performed, and stable quality soldering is automatically achieved with almost no manual work required. It is possible to provide an automatic soldering device that can perform soldering with ease.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, in which FIG. 1 is a schematic side view of the whole, FIG. 2 is a schematic side view in a different operating state from FIG. 1, and FIG. 1 and 2, FIG. 4 is a perspective view, and FIG. 5 is an enlarged side view of the main parts. In the drawing, 1 is a machine frame, 2 is a pallet, 2a is a recess (installation part), 4 is a transport escapement (first transport device), 7 is a flux application station, 1
5 is a lifting device, 20 is a receiving member, 21 is a static flow solder bath, 22 is solder, 23 is a belt conveyor (second transfer device), 25 is a printed circuit board, and B is a take-out device.

Claims (1)

[Scope of utility model registration request] A plurality of pallets each having a mounting portion for mounting a printed circuit board and having through holes formed in the bottom surface of the mounting portion corresponding to the soldering points of the printed circuit board, and the pallets with the printed circuit boards mounted thereon are placed in a flux coating station. a first transfer device that transfers the flux to the static flow soldering tank via the flux application station; and a spray device that sprays flux onto the patterned surface of the printed circuit board through the through hole when the pallet is transferred to the flux application station. When the pallet is transferred above the static flow soldering tank, the pallet is lowered so that one end located on the upstream side of the static flow soldering tank is inclined downward, and then the pallet is transferred to the top of the static flow soldering tank. The pattern surface of the printed circuit board is dipped into the static flow solder tank by gradually lowering the other end located on the downstream side of the solder tank, and after dipping for a predetermined time, the other end is located on the downstream side of the static flow solder tank. an elevating mechanism configured to first raise the other end of the pallet and then raise one end of the pallet located upstream of the static flow soldering tank; an automatic soldering device comprising: a second transfer device for transferring a printed circuit board soldered to the substrate and lifted by the lifting mechanism from above the static flow soldering bath to a take-out position;