JPH02116547A - Conveying device of warpage correcting device of printed wiring board - Google Patents

Abstract

PURPOSE:To make it possible to position and convey both large-sized printed wiring board and small-sized printed wiring board by a method wherein fixed stoppers, which position the printed wiring boards, are provided at certain intervals to the longitudinal direction of a conveyer and, in addition, movable stoppers are provided between the fixed stoppers of the conveyer. CONSTITUTION:Printed wiring boards A are fed in a heating furnace 2 so as to be heated and pressed between cooling plates 5 in order to be able to correct the warpage of the boards. At the conveying of the boards with the conveyer 3, the printed wiring boards A can be conveyed by being positioned with the fixed stoppers 6 and the movable stoppers 7. When the positioning with the movable stoppers 7 is made to be impossible by shifting the movable stopper 7, the boards can be conveyed under the condition that the large-sized printed wiring board A is positioned between the fixed stoppers 6 adjacent to each other to the longitudinal direction of the conveyer 3. Further, by shifting the movable stoppers 7 for positioning, the small-sized printed wiring board A can be positioned between the fixed stopper 6 and the movable stopper 7 adjacent to each other to the longitudinal direction of the conveyer 3.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention relates to a printed wiring board having a resin laminate as a substrate, transported and heated, and then pressed with a cooling plate to correct warpage before being transported. The present invention relates to the structure of a conveyor that conveys printed wiring boards in a wiring board warp correction apparatus.

[Prior art] Printed wiring boards undergo heating, humidification,
Due to the application of various external influences such as pressurization, more or less warping occurs. However, in the past, mounting on printed wiring boards was done using leads, so warping of printed wiring boards did not pose much of a problem, but as surface mounting increases, warping of printed wiring boards has become a major problem. There is.

For this reason, various studies have been made to correct the warpage of printed wiring boards, but the current practice is to correct the warpage by applying force to manually bend the printed wiring board in the direction opposite to the warpage. However, since this method is manual, it requires a lot of manpower and has the problem of poor production efficiency.Also, in order to correct the warpage without causing it to warp back, it is necessary to heat the printed wiring board to correct the warpage. However, since it is done manually, there is a limit to the temperature at which the printed wiring board can be heated, and there is a problem in that warpage cannot be reliably corrected.

As a printed wiring board warping correction device for mechanically correcting this warping, the applicant of this patent previously filed a patent application No. 62-25600.
I applied for No. 5 etc. This device has a heating furnace installed almost in the center of the device body, a conveyor for passing the printed wiring board through the heating furnace, and a conveyor placed above the conveyor to hold the printed wiring board in a standing position on the conveyor. A groove is formed by a guide bar that is placed at the outlet of the heating furnace, and a rewarping means that corrects the warpage by sandwiching the printed wiring board carried out from the heating furnace between the cooling plates, and the printed wiring board is placed in an upright position. The printed wiring board was transported by a conveyor, and the printed wiring board was transported to a heating furnace and heated, and then the printed wiring board was sandwiched between cooling plates and pressed to straighten the warp, and then transported out.

[Problems to be Solved by the Invention] By the way, the conveyor for conveying printed wiring boards is called a verti-en conveyor, but even if the drive of the conveyor is smoothly stopped to convey the printed wiring boards in an upright position, There are cases where the conveyor slips in the longitudinal direction and misalignment occurs, and when misalignment occurs, there is a problem in that the printed wiring board may be damaged.

In order to eliminate this, the conveyor 3
Fixed stoppers 6 that serve as partitions at regular intervals in the longitudinal direction of the
It is also conceivable to provide a This fixed stopper 6
If the printed wiring board A is provided at intervals of the same size as shown in FIG. In the case of printed wiring board A (150 mm), b' of printed wiring board A is shown in Figure 13.
Since the distance between the fixed stoppers 6 is larger than the size of the fixed stopper 6, it is impossible to position and convey it. Furthermore, if the fixed stoppers 6 are provided at intervals of five dimensions as shown in FIG. There was a problem in that the fixed stoppers 6', which were placed on opposite sides, were in the way and the printed wiring board A could only be transported in an inclined state as shown in Figure WIJ14, leading to damage to the printed wiring board A.

The present invention has been made in view of the above points, and an object of the present invention is to provide a printed wiring board that can position and transport both large and small printed wiring boards. The present invention provides a conveying device for a warpage correction device.

[Means for Solving the Problems] In order to achieve the above object, the conveyance device of the printed wiring board warpage straightening device of the present invention includes a heating furnace 2 provided approximately at the center of the device body 1, and a printed wiring in the heating furnace 2. A conveyor 3 that allows the board to pass through, a guide bar 4 that is disposed along the top of the conveyor 3 and holds the printed wiring board A upright on the conveyor 3, and a guide bar 4 that is disposed at the outlet of the heating furnace 2 and that In the printed wiring board warping correction device having a rewarping means for correcting the warpage by sandwiching the printed wiring board A carried out from the cooling plate 5 between the cooling plates 5, the printed wiring board A is placed on the conveyor 3 at regular intervals in the longitudinal direction of the conveyor 3. A fixed stopper 6 is provided for positioning the printed wiring board A.
The present invention is characterized in that a movable stopper 7 is provided between the fixed stoppers 6 of the conveyor 3 and moves so that the reprinted wiring board A is positioned in a positioning state and is not positioned in a positioning state.

[Function] The conveyor 3 feeds the printed wiring board A into the heating furnace 2 and heats it, and at the same time pressurizes the printed wiring board A between the cooling plates 5, so that the warp can be corrected without requiring manual labor. Furthermore, when the printed wiring board A is conveyed by the conveyor 3, it can be positioned and conveyed using the fixed stopper 6 or the movable stopper 7. At this time, if the movable stopper 7 is moved so that it is not positioned by the movable stopper 7, a large printed wiring board A can be positioned and conveyed between the fixed stoppers 6 adjacent to each other in the longitudinal direction of the conveyor 3. Also, movable stopper 7
By moving the conveyor 3 so as to position it, the small printed wiring board A can be positioned between the fixed stopper 6 and the movable stopper 7 that are adjacent to each other in the longitudinal direction of the conveyor 3.

[Example] As shown in Fig. 1(a) and Fig. 1(b), the device main body 1 is equipped with a loading section 10 at the front, an unloading section 11 at the rear, and a heating section 12 at the center. The heating section 12 is provided with a heating furnace 2.

The heating furnace 2 is formed by a circulating hot air dryer or the like in which a blower is driven by a motor 13, and is designed to uniformly heat the printed wiring board A. An inlet and an outlet are formed at the front and rear of the heating furnace 2, and an inlet shutter 14 and an outlet shutter 15 are provided.
Each one can be opened and closed. Further, a conveyor 3 formed by a birch conveyor is provided so as to pass from the loading section 10 through the heating furnace 2 to the unloading section 11. Along the upper side of this conveyor 3, several (for example, 11) guide bars 4 are arranged parallel to the conveyor 3 as shown in FIG. It is installation.

Further, a pressurizing device 19 is provided on the upper surface of the unloading section 11. The pressurizing device 19 is made of several aluminum plates, stainless steel plates, etc. whose front and back surfaces have been polished to a smooth flat surface (for example, 11 plates).
One end of each cooling plate 5 is a fixed cooling plate 5a, and the other one is a movable cooling plate 5b. Of these cooling plates 5, a fixed cooling plate 5a is fixed on the carrying-out part 11, and as shown in Fig. Movable cooling plate 5
b can be freely slid through and suspended.
A connecting member 22 such as a chain or wire is connected to each cooling plate 5 to restrict the gap between the cooling plates 5. For example, each cooling plate 5 is formed to have a thickness of 20 mm, and the length of the connector 22 is set so that the interval between each cooling plate 5 is 7III11 at maximum. And a movable cooling plate 5 located at the end opposite to the fixed cooling plate 5a.
b is the rod 24 of the air cylinder 23 as shown in Figure 3.
By operating the air cylinder 23 and protruding the rod 24, each movable cooling plate 5b is pressed down in sequence, and conversely, by drawing the rod 24 into the air cylinder 23, each movable cooling plate 5b is pressed down. The cooling plates 5b can be successively separated by the action of the connecting tool 22.

In addition, in FIG. 2, 25 is a lifting device formed by an air sill.

The conveyor 3 is a birch-en conveyor, and the conveyor 3 is provided with fixed stoppers 6 at equal intervals in the longitudinal direction of the conveyor 3, as shown in FIG. The fixed stoppers 6 are vertically arranged at intervals corresponding to the intervals between the large printed wiring boards A. The fixed stopper 6 is provided to protrude at a height that does not hit the γ-id bar 4. A movable stopper 7, which can move up and down, is arranged on the conveyor 3 at a position hidden from the fixed stopper 6. In this embodiment, one movable stopper 7 is disposed between each fixed stopper 6, but two or more movable stoppers 7 may be disposed.The specific structure of the movable stopper 7 is shown in FIG. , Figure 7,
It is constructed as shown in FIG. 8 and @FIG. 9. The movable stopper 7 is disposed on one bar 3a of the conveyor 3, and the movable stopper 7 is moved by slidingly inserting a sliding bin 27 with a bar length of 3m into an inclined groove 26 provided vertically in the movable stopper 7. By moving left and right, the movable stopper 7 can be moved up and down. Slanted groove 26
Horizontal grooves 28 are provided above and below. Movable stopper 7
A roller fitting recess 29 is provided at the lower part of the roller. Two idle rods 30 are installed between the left and right sides of the conveyor frame 18, and a movable base 31 is attached to the idle rods 30 so as to be slidable. A seven-leaved loaf 34 that fits into the recess 29 is rotatably mounted.

The operating rod 32 is inserted through the conveyor frame 18, and the tip of the operating rod 32 is connected to the movable base 31.
The 717-roller 34 can be moved from side to side via the movable base 31 by holding the grip 33 at the base end and sliding the operating rod 32. The operating rod 32 is provided with a pair of crocodile parts 35, a collar 36 is provided between the collar parts 35, and the collar 36 is inserted through the insertion hole 37 of the conveyor frame 18 between the pair of collar parts 35. This insertion hole 37 is a pothole, and has a large diameter hole 37a through which the force 2-36 can be inserted, and a small diameter hole 37b through which the locking recesses 38aw38b on both sides of the collar 36 can be inserted. Then, by raising the grip 33 and aligning the collar 36 with the large diameter hole 37a, the operating rod 32 can be moved to lock the small diameter hole 37b in the locking recesses 38a and 38b. Locking recess 38a
When the movable stopper 7 is moved so as to be locked in the small diameter hole 37b, the 7-lead roller 34 is pulled, and the movable stopper 7 is moved so as to protrude upward as shown in FIG.
When the movable stopper 7 is moved so as to be locked in the small diameter hole 37b, the 7-lily loaf 34 is pushed and the movable stopper 7 is moved downward. Such 7 17-
At the position of the roller 34, a plurality of movable stoppers 7 provided at equal intervals in the direction of the force of the conveyor 3 are moved so as to protrude upward and descend downward.

In the present invention, the dipping printed wiring board A to be corrected is as follows:
The substrate is made of a resin MN plate.

That is, a prepreg is created by impregnating a base material such as plus cloth or paper with a face of thermosetting resin such as epoxy resin or phenol uIN and drying it, and then multiple sheets of prepreg and metal foil such as copper foil are combined. After creating a metal foil-clad laminate by stacking and heat-pressing,
Furthermore, by etching or forming holes on the metal foil of this metal foil-clad laminate, a printed wiring board having the resin laminate as a substrate can be obtained.

However, in order to correct the warpage of the printed wiring boards using the lever, first feed the printed wiring boards A one by one onto the conveyor 3 between the idle bars 4 of the loading section 10, and then feed each printed wiring board A between the idle bars 4. By separating and supporting them, a plurality of print sheets NIL@A are set as one set on the conveyor 3 in an upright and lined up state. Since the printed wiring boards A are supported on the conveyor 3 in this upright state, a large number of boards (for example, 10 boards) can be set as one set, thereby ensuring production efficiency. At the same time, since even a small heating furnace 2 can heat a large number of printed wiring boards A at the same time, it is difficult to make the entire apparatus compact.

Also, at this time, the movable stopper 7 can be made to protrude upward or retire downward depending on the size of the printed wiring board A. In other words, when processing a large printed wiring board MIA, the movable stopper 7 is retired and the printed wiring board A is positioned and transported using only the fixed stopper 6.
Big! When processing a small printed wiring board A, the movable stopper 7 is made to protrude 7, and the printed wiring board A is positioned between the fixed stopper 6 and the movable stopper 7 and transported. Then, this printed wiring board A is sent into the heating furnace 2 as the feeder bearer 3 is driven to travel. In the heating furnace 2, each printed wiring board A is supported by the side bar 4 and held in an upright position, and is heated in this state. Heat circulates on both the front and back sides, allowing for efficient and uniform heating. Moreover, since there is an idle bar 4 in each printed wiring board A, a gap is created between each printed wiring board A, and heat is uniformly distributed over the entire surface of each printed wiring board A. can be heated more evenly. As a result, the temperature difference between each part of printed wiring board A is within 5°C, and the temperature difference between the front and back of printed wiring board A is 3°C.
Set within.

Further, the conveyor 3 is operated intermittently at predetermined intervals, and when several sets of printed wiring boards A are sequentially introduced into the heating furnace 2, the first printed wiring board A is removed from the resin glass of the board. The printed wiring board A is heated to a temperature higher than the transition point, and at this point, the printed wiring board A is brought out of the heating furnace 2 to the unloading section 11 as the conveyor 3 is driven.

Here, if the resin constituting the UL laminated board serving as the substrate of printed wiring board A is, for example, epoxy resin, the glass transition point is 120 to 120°C, so printing is performed at a temperature higher than this. This heats the wiring board A.

After being heated in this way, each printed wiring board A that comes out to the unloading section 11 is inserted between each cooling plate 5 and set. Then, the cylinder 23 is actuated, the rod 24 protrudes, slides and presses each movable cooling plate 5b sequentially toward the fixed cooling plate 5a, pinches the printed wiring board A between each cooling plate 5, and presses the cooling plate 5b. 7. Apply pressure on a flat surface to correct the warpage of printed wiring board A. By heating the printed wiring board A to a temperature equal to or higher than the glass transition point of the resin and then applying pressure, it is possible to correct the warpage while removing the residual stress in the printed wiring board. For example, it is sufficient to apply a pressure of 5 to 100 kg to a printed wiring board AI having a size of 30 cI11 x 50 CI11. Also, by bringing the cooling plate 5 into contact with the printed wiring board A in this way, the heat of the printed wiring board A is absorbed by the cooling plate 5 and radiated, and each printed wiring board A is heated to a temperature below the positive transition point. 50 to 6, which can be cooled to a temperature of 50 to 6 and can further handle the printed wiring board A.
It can be cooled down to a temperature of 0°C. After this, actuate the shilling 23 again and move the rod 24 to the shilling 23.
Each movable cooling plate 5b is successively pulled apart by the action of the connecting member 22 and returned to its original state, and as the conveyor 3 operates, each printed wiring board A between the cooling plates 5 is While being moved from between the cooling plates 5 to between the guide bars 4 and carried out, a set of printed wiring boards A coming out of the heating furnace 2 next is inserted between the cooling plates 5 and set.

Thereafter, in the same manner, the printed wiring boards A that are sequentially carried into the carry-in section 10 are heated in the heating furnace 2, and then cooled while being pressurized by the pressurizing device 19. It can be transported from

After heating the printed wiring board A to a temperature above the glass transition point of the resin and correcting the warpage as described above, when the printed wiring board A is cooled to a temperature below the glass transition point,
The printed wiring board will be fixed in a state where the warp has been corrected, so that the warp can be corrected without fail.
1. In a printed wiring board of size 300a+a+.
The warpage of 0II11 can be corrected to 0.11Iffl or less.

FIG. 11 shows another embodiment in which the movable stopper 7 is placed in a positioning state and a non-positioning state for the printed wiring board A. The upper end of the movable stopper 7 is always on the conveyor 3
The sliding pin 27 of the bar 3a is arranged in the horizontal groove 40 of the movable stopper 7 so as to protrude from the top surface of the bar 3a.
is slidably inserted through the movable stopper 7 so that the movable stopper 7 can be moved left and right. There is a cut groove 41 at the top of the movable stopper 7.
are provided at equal intervals on the left and right, and when the cut grooves 41 correspond to the printed wiring board A, the printed wiring board A does not engage the movable stopper 7, and the movable stopper 7 of the above embodiment is lowered. In the same state as above, when the locking portion 42 between the grooves 41 is made to correspond to the printed wiring board A, the printed wiring board A is locked to the movable stopper 7, and the movable stopper 7 of the above embodiment is moved upward. It is supposed to be in the same state as when it was protruded. The structure for moving this movable stopper 7 from side to side may be the same structure as in the above embodiment, or may use another mechanism.

[Effects of the Invention] As described above, in the present invention, the conveyor is provided with fixed stoppers for positioning the printed wiring boards at regular intervals in the longitudinal direction of the conveyor, and the fixed stoppers for positioning the printed wiring boards are provided on the conveyor. A movable stopper is installed between the fixed stoppers of the conveyor that moves so that the reprinted circuit board is not positioned, so if the movable stopper is moved and the movable stopper is not positioned, the conveyor A large printed wiring board can be positioned and conveyed between fixed stoppers that are adjacent in the longitudinal direction, and when the movable stopper is moved to position it, it can be transported between fixed stoppers and movable stoppers that are adjacent in the longitudinal direction of the conveyor. The present invention is capable of positioning a small printed wiring board, is capable of reliably positioning and transporting both large and small printed wiring boards, and can smoothly transport the printed wiring board.

[Brief explanation of the drawing]

Figures 1 (a) and (b) are front and rear perspective views of an embodiment of the device of the present invention, Figure 2 is a front view of the same device, and Figure 3 is the same as the same device. An exploded perspective view of a portion of the device;
Figure 4 is a perspective view of a part of the same device as above, Figure 5 is an explanatory diagram illustrating the fixed stopper and movable stopper provided on the same conveyor as above, and Figure 6 is a plan view of the conveyor as above with movable stopper installed. Figure 7 is a front sectional view of the same as above, and Figure 8 is a front sectional view of the same as above.
Figure (a) is a front cross-sectional view taken at a different position from Figure 7;
FIG. 8(b) is a side view of the insertion hole, FIG. 9 is a side sectional view of the same as above, FIG. The partially omitted front view shown, FIG. 12, FIG. 13, and FIG. 14 are explanatory views for explaining the conventional example. 1 is a main body of the apparatus, 2 is a heating furnace, 3 is a conveyor, 4 is an idle bar, 5 is a cooling plate, 6 is a fixed stopper, and 7 is a movable stopper. Figure 1 (b) 1.￥L equipment body ・〃Idbar Figure 1 (a) 3... Conveyor Figure 9 10th Figure 11 U j/

Claims (1)

[Claims] (1) A heating furnace installed approximately in the center of the equipment body, a conveyor for passing the printed wiring board through the heating furnace, and a conveyor placed above the conveyor to hold the printed wiring board in a standing position on the conveyor. In a printed wiring board warping straightening device having a guide bar and a straightening means arranged at the outlet of a heating furnace to straighten the warped printed wiring board carried out from the heating furnace by sandwiching the printed wiring board between cooling plates, A fixed stopper is provided for positioning the printed wiring board at regular intervals in the direction, and a movable stopper moves from a state where the printed wiring board is positioned to a state where the reprinted wiring board is not positioned. A conveyance device for a warpage correction device for printed wiring boards, characterized in that the conveyor is provided between fixed stoppers of a conveyor.