JPH09237966A - Reflow equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent deformation and vibration of a board during carriage and enable continuous treatment of a reflow process, by installing a board pressing means abutting against the board or leaving it, a board pressing fixing means of a cut tip type, and a board pressing relieving means of a wedge type, in both side end portions of a board carrying path. SOLUTION: On both side end portions of a starting part of the carrying path of a conveyer positioned in a carrying-in port, a tab presser foot 15 pressing a pivotal movement tab 20 vertically to the carrying path is installed. On both side end portions of an ending position of the conveyer, a tab raiser 16 raising a fallen tab 22 is installed. The tab presser 15 abuts against, from above, the board pressing part of the tab 22 against which the part corresponding to the blade of a cut tip abuts, and pushes down the tab 22 in the carrying surface direction. The tab raiser 16 is arranged in the position against which the edge part of the tab 22 abuts returning from the position where board carriage by the conveyer is ended. The tab raiser 16 is a wedge type plate member having an oblique line wherein the form of the side surface is gently inclined.

Description

Detailed Description of the Invention

[0001]

[Table of Contents] The present invention will be described in the following order. TECHNICAL FIELD OF THE INVENTION Conventional Technology Problems to be Solved by the Invention (FIG. 8) Means for Solving the Problems Embodiments of the Invention (FIGS. 1 to 7)

[0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reflow device, which is suitable for application to a component such as a semiconductor device which is soldered to a substrate.

[0003]

2. Description of the Related Art Conventionally, a semiconductor device is mounted on a substrate by soldering electrodes of the semiconductor device and the substrate by a reflow device. In the reflow equipment, the board on which parts such as semiconductor devices are mounted is conveyed from the preheating step to the heating step, and the cream solder is melted by heating the board and then cooled and solidified to solder. Attached. In this case, the substrate is carried by placing it on a conveyor or the like.

[0004]

By the way, the conventional reflow apparatus has a problem that the quality of the substrate deteriorates due to warping of the substrate which has been heated to a high temperature during transportation. Further, as shown in FIG. 8A, since the substrate P is simply placed on the conveyer C, there is a problem in that the components on the substrate are displaced due to the vibration of the device. . Further, as shown in FIG. 8B, there is also a problem that the substrate deformed by heat is blown by the hot air of the fan used in the reflow process during transportation and falls from the conveyor.
As a transfer device used to transfer the substrate in the reflow device in order to solve this problem, for example, the transfer device disclosed in Japanese Patent Laid-Open No. 5-254688 is facing both end portions of the substrate along the transfer direction. Clamping means for sandwiching and supporting the substrate from both sides by the disposed transport belt is provided.
This prevents the substrate from warping while being transported in the heating chamber and prevents the substrate from dropping from the transport belt.

However, in this transfer device, since the pin-shaped holding means is fixed to the transfer belt, the substrate cannot be held in the holding means while the transfer belt is performing the transfer operation. Therefore, each time the substrate is placed on the transfer belt, the transfer operation is temporarily stopped, and the flow of the production line must be stopped each time.

Further, as shown in FIG. 8C, in order to prevent the substrate from dropping from the transport belt, it is conceivable to support the substrate P to be transported from below by a net N. However, in this case, the semiconductor device M is formed on the lower surface of the substrate P.
There is a problem that parts such as the above cannot be mounted. In addition,
The reflow device disclosed in Japanese Patent No. 6-045747 supports both end portions of the substrate by a pair of guide rails provided on the lower surface side of the substrate and presses the upper surface of the substrate with a leaf spring to convey the substrate. The inside of the substrate is prevented from falling. By the way, in this reflow apparatus, a substrate is rotated by a timing belt provided on the lower surface of the substrate, and the substrate is pushed by a feed pin protruding from the timing belt. In this case, the feed pins are arranged at constant intervals according to the processing speed and the processing procedure of the substrate, so that the size of the substrate to be processed is limited by the pitch between the feed pins. . Further, there is a problem that a substrate having a size larger than the pitch between the feed pins cannot be transported.

Further, since the substrate is not conveyed unless the feed pin reaches the predetermined position for pushing the substrate, the processing interval of the reflow process is determined by the pitch between the feed pins. Therefore, for example, when the substrate is randomly carried out from the previous process of the reflow process, the processing intervals cannot be adjusted in the reflow process. Therefore, in the reflow process, the movement of the conveyer must be stopped in order to adjust the position of the feed pin of the conveyer conveyor in accordance with the timing of loading the substrate from the previous process. As described above, in the reflow process, when the substrate loading is random, the substrate processing must be frequently stopped, which causes a problem that the flow of the production line is delayed.

The present invention has been made in consideration of the above points, and prevents the substrate from being deformed during the transfer in the reflow process and the vibration of the substrate, and the process of the reflow process is performed depending on the timing of the substrate loading from the previous process. The present invention is intended to propose a reflow apparatus that can be continuously performed.

[0009]

In order to solve such a problem, in the present invention, after the substrate is heated by passing the substrate through the heating chamber to melt the solder on the substrate,
In a reflow device for performing a soldering process by cooling, a transfer means for mounting and transferring a board, and the board provided at both end portions of a transfer path of the transfer means so as to freely come into contact with or separate from the board. Board holding means for holding and fixing the board holding means with the transfer means, a tip-shaped board holding means for pushing down the board holding means on the board, and a wedge for holding the board holding means above the board. When the substrate is passed through the heating chamber, the substrate holding means is pushed down onto the substrate according to the shape of the substrate holding fixing means to easily fix the substrate to the transfer means. When the soldering is completed, the fixing of the board is easily released by pushing up the board holding means from above the board according to the shape of the board holding release means.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings.

In FIG. 1, reference numeral 1 denotes a reflow apparatus according to the present invention as a whole, which is a substrate P which is conveyed from the previous step by an external conveyor 2 for carrying components such as a semiconductor device M. Then, the cream solder is melted by being delivered to the conveyor 3 for transportation inside the apparatus and transported in the preheating chamber 4 and the heating chamber 5 to heat the substrate P.
Then, the electrodes on the substrate P and the electrodes of the semiconductor device M are soldered to each other by cooling the substrate P in a cooling chamber (not shown) and solidifying the molten solder.

A substrate P is provided near the carry-in port 6 of the reflow apparatus 1.
Further, a UV (Ultra Violet) lamp 7 for solidifying an adhesive for fixing the semiconductor device M and a forced exhaust fan 8 for exhausting hot air of the UV lamp 7 are provided.
The preheating chamber 4 and the heating chamber 5 are partitioned by partition walls 4A and 5A, respectively, and the substrate P is conveyed in the direction of the arrow between them by the conveyor 3 through which the substrate P passes.
A heater 1 for heating the substrate P is provided below the conveyor 3.
0, a fan 11 for convection of heat generated by the heater 10, and a fan motor 12 for driving the fan 11. Further, the heating chamber 5 is provided with a flux exhaust duct 13 for exhausting a flux gas generated by soldering.

As shown in FIG. 2, the conveyor 3 is formed by chain-connecting a plurality of transport pins 20 and is rotatably driven by a motor (not shown) via a pulley 21 (FIG. 1). Each of the transport pins 20 has a connecting pin 20A for connecting the pins, and a support having a radius smaller than that of the connecting pin 20A by about the thickness of the substrate P. It is formed from the pin 20B. Rotation tabs 22 for clip-fixing and pressing the substrate P between the support pins 20B are rotatable on both outer sides of the chain-connected transport pins 20 in a direction orthogonal to the transport direction of the conveyor 3. Is attached to.

As shown in FIG. 3, the rotating tab 22 has a supporting portion 23 protruding from the rotating shaft AX of the rotating tab 22,
It is composed of a substrate pressing portion 24 which is bent at an acute angle rather than a right angle via the support portion 23. Incidentally, the rotating tab 22 is formed in a wire-like shape whose material is spring copper. The wire shape can reduce the weight of the rotating tab 22 itself. The rotation axis AX of the rotation tab 22 is connected to the connecting pin 20A of the transport pin 20 so that it is substantially parallel to the transport surface of the substrate when the conveyor 3 is rotated and the transport pin 20 is located along the transport surface of the substrate. It is attached.

Here, as shown in FIGS. 1 and 4, tabs for pressing the rotating tabs 22 are provided at both end portions of the start portion of the convey path of the conveyor 3 located at the carry-in entrance 6 substantially perpendicular to the convey path. A presser foot 15 is provided, and tab risers 16 for raising the tilted turning tabs 22 are provided at both end portions of the end position of the conveyor 3, respectively. As shown in FIG. 2, the tab retainer 15 has a shape like a cutting edge of a sword, and is pressed from above with respect to the substrate retaining portion 24 of the rotating tab 22 that abuts by a portion corresponding to the blade of the cutting edge. When pressed, the rotating tab 22 is pushed down in the transport surface direction. That is, the tab retainer 15 pushes down the rotating tabs 22 that are fed along with the rotation of the conveyor 3 from above and pushes them down one after another. The both end portions of P are brought into contact with each other from above and are clamped to fix the clips one by one. In this way, by fixing the substrate P being transported by the rotating tab 22,
It is possible to prevent the substrate being transported from vibrating and deforming due to heat. Further, in this case, since the turning tabs 22 clip and fix only both side end portions of the substrate P, components can be mounted also on the back surface of the substrate P.

Further, as shown in FIG. 5, the tab raising 16 is arranged at a position where the edge portion of the rotating tab 22 which is forwarded at the position where the substrate transfer by the conveyor 3 is finished is brought into contact. The tab raising 16 is made of a wedge-shaped plate member having a slanted side surface, and the bottom of the slanted side is located at the exit 25 of the conveyor 3.
The conveyor 3 is installed substantially vertically to both end portions on both sides of the conveyor surface. Here, the substrate P, which has completed the reflow process, is transported in a state where the clip is fixed, and the tab is raised 1
When the installed position of 6 is reached, the substrate pressing portion 24 of the revolving tab 22 fed forward is pushed up one after another along the hypotenuse of the tab raising 16 and moves. That is, the rotation tab 22 is rotated about the rotation axis AX as a fulcrum shaft and is raised up to a predetermined angle, so that the substrate P is released from the pressed state and the substrate fixation is released.

Here, by making the engaging and supporting portion 23 of the rotating tab 22 have an appropriate length as a play, the transport pin 20 is provided.
An appropriate gap can be created between the and. As a result, in the state where the turning tab 22 fixes the board P to the clip,
The tab raising 16 can be easily inserted between the transport pin 20 and the rotating tab 22.

Here, the pressing operation of the rotating tab 22 by the tab retainer 15 and the raising operation of the rotating tab 22 by the tab raising 16 are performed according to the rotation of the conveyor 3 regardless of whether the substrate P is on the conveyor 3 or not. Turning tab 22
Against one another. That is, no matter how long the substrate P is transported to the reflow device 1, the turning tabs 22 are sequentially moved to the both end portions of the substrate by the tab retainer 15 provided at the carry-in port 6 regardless of the transportation interval. Fix the clip. As a result, in the reflow process, the process can be delivered to the subsequent process while maintaining the processing interval from the previous process, and thus continuous process processing without stopping the flow of the production line can be realized.

In the above structure, when the substrate P on which the components such as the semiconductor device M, which has been processed in the previous process, is placed, is transferred from the carry-in port 6 onto the conveyor 3 in the reflow apparatus 1, the substrate P is The both ends are sequentially clipped and fixed by the tab retainer 15. That is, when the pressing portion of the tab retainer 15 hits the substrate retaining portion 24 of the rotating tab 22 at a predetermined angle, the substrate retainer portion 24 is gradually pushed down by the tab retainer 15 onto the transport surface. . As a result, both ends of the substrate P conveyed on the conveyor 3 are clipped and fixed one after another. Since both ends of the substrate P are clipped and fixed in this manner, it is possible to prevent the substrate P transported in the reflow apparatus 1 from being warped and deformed during the heat treatment, and the occurrence of substrate vibration. Further, it is possible to prevent the mounting position of the component on the substrate P from being displaced due to vibration during the transportation of the substrate. Further, since the deformation of the substrate is prevented, the substrate P will not drop from the conveyor 3.

When the board P has been processed in the reflow process and the board P to which components such as the semiconductor device M have been soldered is conveyed to the carry-out port 25, the rotary tab 22 is lifted by the tab raising 16. The substrates P are raised one after another, whereby the fixation of the substrate P is released. That is, when the clip-fixed substrate P is conveyed to the carry-out port 25, the substrate pressing portion 24 of the rotating tab 22 that is forwarded along with the rotation of the conveyor 3 conforms to the shape while coming into contact with the tab riser 16. Move.
As a result, the board pressing portion 24 is gradually raised to a predetermined rotation angle along the inclined shape of the tab raising 16,
As a result, the fixation of the substrate is released.

According to the above construction, when the substrate P on which the components such as the semiconductor device M are mounted is carried into the reflow device 1, the rotary tab 22 which is fed along with the rotation of the conveyor 3 for transportation is rotated. By sequentially pushing down with the tab retainer 15 having the shape of a sword's tip, the substrate P is clipped and fixed, whereby the displacement of the components on the substrate due to the vibration generated in the device and the deformation of the substrate due to heat. Can be prevented. When the substrate P is carried out after the reflow process, the substrate P, which is clipped and fixed by the rotating tab 22, is sequentially raised by the wedge-shaped tab raising 16 as the conveyor 3 rotates. As a result, the fixed state is released. Thus, by simply rotating the rotary tab 22 to the position where the tab retainer 15 or the tab raising 16 is installed along with the rotation of the conveyor 3, the substrate P is fixed or fixed depending on the shapes of the tab retainer 15 and the tab raising 16. The fixation can be easily released.

Further, according to the above-mentioned embodiment, the components can be mounted on both sides of the substrate P by clipping and fixing only both side end portions of the substrate P being conveyed. Further, according to the above-mentioned embodiment, the substrate P which is being transported is the tab holder 1
Since the clip is fixed in order from the part that reaches position 5, continuous reflow processing can be executed regardless of the carry-in interval from the previous process, and thus the flow of the entire production line including the reflow process can be performed. It can always be done smoothly without stopping at.

In the embodiment described above, the turning tab 2
The case where the wire 2 has a wire shape has been described, but the present invention is not limited to this. For example, the rotating tab 30 shown in FIG.
As described above, the substrate pressing portion may be planar. This can increase the strength of the turning tab. Further FIG.
Like the rotating tab 31 shown in (B), the tip of the substrate pressing portion may be bent. By using this rotation tab 31, the substrate P can be reliably fixed to the support pin 20B as shown in FIG.

Further, in the above-mentioned embodiment, the case where the tab for fixing the substrate P is a rotating tab has been described, but the present invention is not limited to this, and for example, it extends and contracts in the vertical direction with respect to the transport pin 20. It may have a structure like this.
As a result, the same effect as that of the above-described embodiment can be obtained. Further, in the above-mentioned embodiment, the case where the reflow device is used in the air reflow device has been described, but the present invention is not limited to this and can be applied to a nitrogen reflow device and the like.

[0025]

As described above, according to the present invention, the substrate is held between the carrier and the carrier, which is provided at both ends of the carrier path of the carrier so as to come into contact with or separate from the substrate. Substrate pressing means for fixing the substrate pressing means, the tip-shaped board pressing fixing means for pushing down the board pressing means on the board, and the wedge-shaped board pressing releasing means for lifting the board pressing means above the board. Thus, when the board is passed through the heating chamber, the board pressing means is pushed down onto the board according to the tip shape of the board pressing and fixing means so that the board pressing means is easily fixed to the transfer means and the soldering is completed. In this case, the substrate can be easily released from the fixing by pushing up the substrate pressing means from above the substrate according to the wedge shape of the substrate pressing releasing means. Thus, it is possible to realize a reflow apparatus capable of suppressing the vibration and dropping of the substrate during the transportation in the heating chamber, preventing the deformation of the substrate in advance, and continuously performing the substrate processing.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing an overall configuration of a reflow apparatus according to the present invention.

FIG. 2 is a schematic diagram showing a conveyor and a tab retainer.

FIG. 3 is a schematic diagram showing a tab.

FIG. 4 is a schematic diagram showing a conveyor.

FIG. 5 is a schematic diagram showing a turning tab and a tab raising.

FIG. 6 is a schematic diagram showing a rotating tab.

FIG. 7 is a schematic diagram used for explaining fixation of a substrate by a rotating tab.

FIG. 8 is a schematic diagram showing conventional substrate transfer.

[Explanation of symbols]

1 ... Reflow device, 2, 3, C ... Conveyor, 4 ...
Preheating chamber, 5 ... Heating chamber, 6 ... Outgoing port, 7 ... UV
Lamp, 8 ... Forced exhaust fan, 10 ... Heater, 11
…… Huan, 12 …… Motor, 20 …… Transport pin, 20
A ... Connection pin, 20B ... Support pin, 21 ... Pulley, 22, 30, 31 ... Rotating tab, M ... Semiconductor device, P ... Substrate.

Claims (3)

[Claims] 1. A reflow apparatus for carrying out a soldering process by heating a substrate by passing the substrate through a heating chamber to melt solder on the substrate and then cooling the solder to carry the substrate. A carrier means and a substrate pressing means for pressing and fixing the substrate between the carrier means, which is provided at both ends of a carrier path of the carrier means so as to come into contact with or separate from the substrate. A tip-shaped substrate retainer fixing means that pushes down the substrate retainer onto the substrate when the substrate is carried in, and a wedge that pushes up the substrate retainer from the substrate when the substrate is unloaded. And a substrate pressing release means having a shape. 2. The substrate pressing means has a substrate pressing portion that presses the substrate from the upper surface, and the substrate pressing portion is rotatably attached in a direction substantially orthogonal to the transfer direction of the substrate. The reflow apparatus according to claim 1, wherein: 3. The transport means transports the substrate by placing the lower surfaces of both side ends of the substrate on transport pins connected in a chain, and driving the transport pin to rotate. The reflow device according to claim 1.