JP2594166B2 - Curing equipment - Google Patents

Description

The present invention relates to a curing device for bonding or soldering an electronic component to a printed circuit board conveyed by a conveyance device using an ultraviolet lamp or an infrared heater.

(B) Conventional technology In this type of curing device, a printed circuit board on which components such as chip resistors and chip capacitors are placed is sent to the curing device on a conveyor, and the chip components are fixed to the printed circuit board by applying high heat. Is to let
A reflow device, an adhesive curing device for fixing chips, and the like are used.

The curing device usually adjusts the conveyor width of the pair of conveyors to the dimensions of the printed circuit board to support the printed circuit board, and continuously arranges the printed circuit boards and sends them into the curing device.

However, due to a mistake in adjusting the conveyor width of the conveyor,
The printed circuit board may come off and fall into the curing device, or the conveyed material on the conveyor such as the printed circuit board may fall because the printed circuit board is deformed by the high temperature in the curing device.

In this case, it is late to notice the mistake of adjusting the conveyor width,
Many defective products are generated, and an accident that a falling object burns in the curing device is caused.

Therefore, conventionally, in order to prevent such an accident, an operator monitors whether or not the operator has fallen.

However, this method is troublesome, and also takes a long time from when the conveyed object is dropped to when the conveyed object is noticed, resulting in a disadvantage that many defective products are generated.

In Japanese Utility Model Application Laid-Open No. 63-177076, a light-emitting element and a light-receiving element are arranged at the entrance and exit of the curing device below the conveyor, respectively. When the printed circuit board falls, light is blocked by the printed circuit board. There is a technique for detecting a drop of a substrate by using the method.

However, also in this case, since the falling posture of the printed circuit board is different, it is difficult to set the mounting position of the light emitting element and the light receiving element, and sometimes the printed circuit board cannot be detected even though it has fallen.

(C) Problems to be Solved by the Invention Accordingly, it is an object of the present invention to provide a curing device with a mechanism for reliably detecting that a printed circuit board has fallen and for notifying an operator of the fact.

(D) Means for Solving the Problems Accordingly, the present invention relates to a curing device for bonding or soldering electronic components to a printed circuit board conveyed by a conveying device using an ultraviolet lamp or a far-infrared heater. Detecting means for detecting whether or not the substrate has been unloaded from the substrate unloading section; determining means for determining that the substrate has dropped if the detecting means detects that the substrate has not been unloaded; And control means for operating a discharge conveyor for discharging the dropped substrate when it is determined that the substrate has fallen.

Also, in a curing device for bonding or soldering electronic components to a printed board conveyed by a conveyance device using an ultraviolet lamp or a far-infrared heater, the presence / absence of a substrate provided in a substrate carrying-in portion and being carried in is determined by the carrying device. A board carry-in detecting means for detecting every transport distance of the board, a board carry-out detecting means provided in a board carry-out portion and detecting presence or absence of a board to be carried out, and the board being transported between the two detecting means while the board is carried. Storage means having the same number of memories as the number of times of detection by the carry-in detection means and storing the data detected by the board carry-in detection means while sequentially shifting the data to the memories;
Comparing means for comparing the data in the last memory of the storage means with the detection result by the board unloading means; and the data content stored in the storage means is "Yes" from the comparison result by the comparing means, and the board unloading means The detection result by the detection means is “Nothing”
And determining means for determining that the substrate has fallen from the transfer device in the case of.

(E) Operation From the above configuration, when the judging means judges that the substrate has dropped because the detecting means has detected that the substrate has not been conveyed from the substrate, the control means operates the discharge conveyor to discharge the dropped substrate. I do.

Further, predetermined data detected by the board carry-in detection means and stored in the storage means is compared with a detection result detected by the board carry-in detection means by the comparison means. Then, the judging means judges that the substrate has dropped if the result of the comparison is the content of the predetermined data stored in the storage means or “present” and the result of detection by the board unloading detecting means is “absent”.

(F) Embodiment One embodiment of the present invention will be described below with reference to the drawings.

(1) is a curing device, which comprises a base (2), a substrate transport section (3) as a transport apparatus, and an adhesive / curing section (4). A pair of conveyors (5) are provided in the transport unit,
The printed circuit board (8) is conveyed by the drive motor (40) via the drive sprocket (6) and the driven sprocket (7). Although not shown, a solder paste is applied to the printed circuit board (8) by a screen printing machine, and an ultraviolet curable adhesive is applied by an adhesive application device, and, for example, chip-shaped electronic components are temporarily fixed thereon. I have.

An adhesive / curing section (4) is provided above the transport section (3). The adhesive / curing section (4) has an ultraviolet lamp storage chamber (9) and a far infrared heater storage chamber (1).
0) are sequentially arranged.

In addition, a storage room for a near-infrared heater may be provided next to the far-infrared heater storage section (10).

The heater storage chamber (10) has a top plate portion having an insulating wall (10).
A), a panel-type far-infrared heater (11) is provided at predetermined intervals above and below the conveyor (5), and an exhaust duct (12) is provided. .

The ultraviolet lamp storage chamber (9) and the heater storage chamber (10) are separated by a heat insulating wall (13) provided at a position close to the far infrared heater (11). A cylindrical ultraviolet lamp (14) arranged in the lamp storage chamber (9) so that its longitudinal direction is orthogonal to the flow direction of the printed circuit board (8) is above the conveyor (5). Located at the location. Above the lamp (14), a reflector (15) having a semicircular cross section is disposed with a length slightly longer than the length of the lamp (14) in the longitudinal direction. An exhaust duct (17) provided with a cooling exhaust fan (16) is provided above the reflector (15).

The upper part of the exhaust duct (17) has an opening (18) communicating with the outside of the curing device. An opening (19) is formed in the upper part of the reflection plate (15) so as to communicate with the duct (17), and the outside plate (9A) of the storage chamber (9) also has an outside air inlet (9). 20) is formed.

(21) is an air shield, which is formed between the ultraviolet lamp (14) and the conveyor (5) with a material that transmits ultraviolet light, for example, quartz glass. The shield (21) forms a bottom surface of the lamp storage chamber (9) so that hot air from the heater storage chamber (10) is not substantially taken into the lamp storage chamber (9). It is provided over the entire area or substantially the entire area of the bottom surface.

(22) is a mesh type discharge conveyor, which discharges the printed circuit board (8) dropped from the conveyor (5) by a drive motor (23) through a driving sprocket (24) and a driven sprocket (25).

 Hereinafter, the substrate drop detecting means will be described.

(30) in FIG. 2 is a substrate carrying-in detecting means comprising a reflection type photo sensor provided in the vicinity of the substrate carrying-in portion of the curing device (1), and detects "present" or "absent" of the printed circuit board (8). (31) is a substrate unloading detecting means similarly provided near the substrate unloading section.

Numeral (32) is a RAM as storage means including a shift register (33), and N shift registers (33) are provided over substantially the entire transport area of the curing device (1).

 Here, N in this embodiment will be obtained.

First, the distance of the transport path of the curing device (1) (the distance between the substrate carry-in detection means (30) and the substrate carry-out detection means (31)) is set to 3700.
[Mm].

The number of slits of a rotating plate (not shown) that is rotated synchronously with the drive motor (40) is six.

 The number of teeth of the sprockets (6) and (7) is 22.

The chain pitch of the conveyor (5) is set to 9.525 [mm].

As a result, the distance of the printed circuit board (8) advanced by one rotation of the rotating plate is 22 × 9.525 [mm] = 209.55 [mm] and 1
The distance of the printed circuit board (8) that advances per slit is 34.925.
[Mm].

Accordingly, the presence or absence of the printed circuit board (8) is detected every 34.925 [mm].
00 [mm] ÷ 34.925 [mm] ≒ 106 pieces (1,2,3 ... N-1, N = 1
06). In this embodiment, assuming that the length of the printed circuit board (8) in the transport direction is 100 [mm], the board carry-in detection means (30) performs presence / absence detection twice for one printed circuit board (8). Will be.

Then, the substrate carry-in detection means (30) and the substrate carry-out detection means (31) perform the print circuit board (8) every predetermined time (time during which the substrate (8) is conveyed by a predetermined conveyance distance of one slit rotation of the rotating plate). The presence / absence detection work is performed. Then, for example, if the printed board (8) is detected as “present” by the board carry-in detection means (30), “present” is set in the memory 1.
Next, if the detection result by the board carry-in detection means (30) after the lapse of a predetermined time is "Yes", "Yes" is set in the memory 1. Next, the data “present” already set in the memory 1 is shifted to the memory 2. Further, if the result of detection by the board carry-in detection means (30) after the lapse of a predetermined time is "absent", the memory is set to "absent". The data “present” already set in the memory 1 is shifted to the memory 2, and the data “present” set in the memory 2 is shifted to the memory 3. Hereinafter, similarly, the result detected by the board carry-in detection means (30) is sequentially set in the memory 1. Then, the already set data is sequentially shifted.

FIG. 2 is a control block diagram relating to the curing device (1) of the present invention. A CPU (35) as control means for controlling the entire device is provided on a bus line (34), and all operations of the device are performed. ROM (36) for storing a given program according to the above, and the RAM for storing the presence or absence of a printed circuit board (8) in a transport path.
(32), a CRT interface (3) connecting the I / O interface (37) and the CRT (38) to the bus line (34).
9) are connected respectively.

The I / O interface (37) has a drive motor (23) of a discharge conveyor (22) for discharging the dropped printed circuit board (8), a board carry-in detecting means (30), a board carry-out detecting means (31), Drive motor (40) of conveyor (5) for transporting printed circuit board (8), warning indicator (41) or warning buzzer (42) as warning means and keyboard (43) as input device, start to start operation An operation unit (46) including a key (44) and a stop key (45) for stopping the operation is connected to each.

 Hereinafter, the operation will be described.

The presence or absence of the printed circuit board (8) conveyed from the upstream side (left side in FIG. 1) is sequentially detected by the board carry-in detection means (30) at the predetermined time intervals.

Then, the data is sequentially stored in the shift register (33) in the RAM (32). That is, the first data is stored in the memory 1 of the shift register (33). Next, the second data is stored in the memory 1 and shifted to the first memory 2 described above. Hereinafter, data is similarly stored in the shift register (33).

Printed circuit board (8) placed on conveyor (5)
Are sequentially conveyed. At this time, the adhesive applied to the printed circuit board (8) is cured by both the ultraviolet lamp (14) and the far-infrared heater (11), or similarly applied. The solder paste thus obtained can be preheated and melted. The adhesive can be cured by an ultraviolet lamp (14) and the solder paste can be preheated and melted by a far-infrared heater (11).

At this time, the hardening, preheating and melting can be performed in a state where the hot air in the far-infrared heater storage chamber (10) is not substantially taken into the ultraviolet lamp storage chamber (9) by the shield (21). That is, the outside air introduced from the outside air intake (20) by the exhaust fan (16) exchanges heat with the ultraviolet lamp (14) and is exhausted through the opening (19) and the opening (18) of the reflector (15). Is done.

At this time, since the shielding body (21) can transmit ultraviolet rays, it does not hinder the above-described curing, preheating and melting.

Thereafter, after the work is continued and a predetermined time elapses (a time until the first data detected by the board carry-in detecting means (30) is shifted to the memory 106), the printed board (8) is moved by the board carry-out detecting means (31). Is detected or not, and the result and the data set in the memory 106 are compared with the CPU.
The comparison is made by comparison means (not shown) in (35). The comparison result indicates that the detection result by the board unloading detection means (31) is “absent”.
If the data in the memory 106 is “present”, C
The determination means (not shown) in the PU (35) determines that the printed circuit board (8) has fallen in the transport path.

Then, based on the determination result, the CPU (35) notifies the worker via a warning indicator lamp (41) or a warning buzzer (42) as warning means.

The operator immediately activates the drive motor (23) and uses the discharge conveyor (22) to drop the printed circuit board (8).
To discharge. If it is determined that the board has dropped, the CPU (35)
By driving the drive motor (23) and discharging the printed circuit board (8) out of the curing device (1) by the discharge conveyor (22), automation becomes possible. In this case, the operation of the motor (23) may be stopped after a lapse of a predetermined time (considering the time until discharging) using a timer (not shown).

When the detection result by the board unloading detection means (31) is “absent” and the data in the memory 106 is “absent”, the detection result is “present”, and the data in the memory 106 is “absent”. If "Yes", the curing operation is continued.

Here, in the present invention, the presence or absence of the printed circuit board (8) is detected for each slit of the rotating plate.
If the distance traveled by the printed circuit board (8) during the rotation of the slit is somewhat shorter than the length of the printed circuit board (8) in the transport direction, the presence or absence of the printed circuit board (8) can be reliably detected. Therefore, there is no need to change the detection interval in accordance with the length of the various printed circuit boards (8), and the usability is good. Of course, one substrate 1 detection may be used.

(G) Effect of the Invention As described above, according to the present invention, it is possible to reliably detect that the printed circuit board has fallen in the curing device and to reliably discharge the dropped substrate. Thus, the substrate can be prevented from burning in the apparatus.

[Brief description of the drawings]

1 and 2 are a front view and a control block diagram of a curing device according to the present invention. (1) ... curing device, (30) ... substrate loading detection means,
(31) ... board unloading detection means, (32) ... RAM, (33)
... shift register, (35) ... CPU.

Claims (2)

(57) [Claims] In a curing apparatus for bonding or soldering electronic components to a printed circuit board conveyed by a conveying device by an ultraviolet lamp or a far-infrared heater, the substrate carried in from a substrate carrying-in part is carried out from a substrate carrying-out part. Detecting means for detecting whether or not the substrate has been unloaded; determining means for determining that the substrate has dropped if the detecting means has detected that the substrate has not been unloaded; and determining that the substrate has fallen by the determining means. And a control means for operating a discharge conveyor for discharging the dropped substrate. 2. A curing device for bonding or soldering an electronic component to a printed circuit board conveyed by a conveying device by an ultraviolet lamp or a far-infrared heater. A substrate carry-in detection unit that detects at every predetermined conveyance distance by the apparatus, a substrate carry-out detection unit that is provided in a substrate carry-out unit and detects the presence or absence of a substrate to be carried out, and while the substrate is carried between the two detection units. Storage means having the same number of memories as the number of times of detection by the substrate carry-in detection means, and storing the data detected by the substrate carry-in detection means while sequentially shifting the data to each of the memories; and Comparing means for comparing the detection result of the data with the board unloading detecting means; and determining that the data content stored in the storage means is "Yes" based on the comparison result of the comparing means. Ri curing device the detection result by the substrate carrying-out detecting means, characterized in that the substrate from the conveying device when a "no" is provided with determining means for determining that the falling.