JPH05242948A - Cover removing device and cover removing method - Google Patents

Abstract

PURPOSE:To prevent the insulating layer of a board from being broken by a laser beam by providing a movable shielding member near the bonding posi tion between covered wires and the board when light is irradiated to remove a cover near the bonding position. CONSTITUTION:A bonding iron 41 is located above the pad 32 of a board 31. Twin wires 27 are held by a hand 42 serving as a one-end holding means and extracted to the preset position from a feeding means, they are held by a hand 43, then a covered wire 27a to be removed with a cover is separated. A shielding plate 39 is moved below the wire 27a and above the pad 32 by an air cylinder 37. A laser beam 28 is applied to the intermediate position of the wire 27a between the hands 42, 43. The cover of the wires 27 is removed by the length of about 100mum by the laser beam 28, and a wire portion 27b is exposed. The shielding plate 39 prevents the laser beam 28 from being irradiated on the printed board 31.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for removing coating used for bonding a coated wire on a substrate.

In recent years, in electronic equipment such as computers, the printed circuit boards to be used have been made to have high density wirings and multi-layers as the operation speed has been increased. When a defect in the wiring portion of the printed circuit board is discovered or a design is changed, it is expensive to remake a new one. Therefore, a fine wire is used to correct the printed circuit board. Therefore, reliable automation of work is desired.

[0003]

2. Description of the Related Art Conventionally, wire wiring work for repairing a printed circuit board has often been performed manually, but automation has come to be performed. In this case, as the density of the printed circuit board increases and the distance between pins is shortened, thin wires with a diameter of 0.1 mm or less are used, and wire positioning accuracy of tens of μm is required. There is.
Further, for noise countermeasures, twin wires for signals and ground are used, and the wires are covered to avoid contact between the wires and a pad.

Further, as the printed board becomes multi-layered, both the insulating layer and the metal pattern become thin, and the pressing force against the printed board must be less than several kg / mm ² in order to prevent damage to the insulating layer and the like. The condition must be met.

FIG. 4 shows a diagram for explaining the conventional coating removal. As described above, when the pressing force on the printed circuit board must be reduced, the as-coated wire cannot be directly bonded,
Bonding is performed after removing the coating.

In FIG. 4, the wire 11 is a supply means 12.
Further, the coating is removed, and the coating is removed by the coating removing means 12a by laser light or the like to be supplied. The supply is the wire 1 with the coating removed by being gripped by the first hand 13.
Pad 1 of which the portion 1a is about 0.1 mm square of the printed board 14
It is performed so as to be located above 5, and the position is fixed by being gripped by the second hand 16.

Then, the wire 11a is sandwiched and clamped by forceps 17a and 17b, and the wire 11a is bonded onto the pad 15 by the bonder iron 18.

In order to position the wire 11 at a position about 0.1 mm above the pad 15 of the printed board 14 for bonding, the wire 13 is gripped by the hands 13 and 16, and the grip point of the wire 11 of the hands 13 and 16 is determined. It is necessary to keep the length from the bottom to 0.1 mm or less.
Since it is necessary to make 3 and 16 a precise mechanism, realization is difficult. Therefore, in the state shown in FIG. 4, the wire 11 is grasped by the hands 13 and 16 at a height of several mm from the printed board 14 at a distance of several tens mm, and is moved in the axial direction of the wire 11 to apply force control. deep. Then, the vicinity of the bonding point is restrained from above by the forceps 17a and 17b and moved downward to be positioned at 0.1 mm above the pad 15 of the printed board 14.

This method facilitates the realization of a mechanism for keeping the distance below the wire gripping points of the hands 13 and 2 by about 2 mm, and the forceps 17a and 17b are used to enable positioning.

[0010]

However, when the coated twin wire is used, the positional accuracy in the axial direction of the wire is several tens of μ in the coating removal treatment and the subsequent positioning to the pad.
m is required. Moreover, since the wire is thin and the elastic limit of the pulling force is small, the wire may be plastically deformed when the accuracy of the force control of the pulling force is larger than the elastic limit.
In addition, the wire is thin and the coating is slippery, which can cause it to slip relative to the hand it is gripping. Due to such plastic deformation and slippage of the wire, there is a problem that the axial positional accuracy of several tens of μm cannot be realized.

Further, when the coating removal by the laser beam is performed near the bonding position, the laser beam is also applied to the printed circuit board 14, and the insulating layer mainly made of polyimide is destroyed to cause a short circuit. There is a problem of being a cause.

Therefore, the present invention has been made in view of the above problems, and an object of the present invention is to provide a coating removing apparatus which prevents the destruction of the insulating layer of the printed board by the laser beam.

[0013]

[Means for Solving the Problems] The above problems are
When bonding two closely-covered coated wires, the closely-coated cable that is gripped and supplied by the gripping means is separated, and one of the coated wires is irradiated with light to remove the coating. In irradiating the coated wire to be stripped with the light in the vicinity of the bonding position, a shield member that is movable between the coated wire to be stripped and the substrate and near the bonding position is located. Will be solved.

[0014]

As described above, when the coating is removed by irradiating light near the bonding position, the shielding member is positioned between the coated wire and the substrate and near the bonding position. Therefore, when the coating is removed, the shield member does not irradiate the substrate with light, and the destruction of the insulating layer is prevented. This facilitates positioning of the stripped wire portion on the bonding position.

That is, the coating can be removed in the vicinity of the bonding position where the positioning is easy, without destroying the insulating layer of the substrate.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a block diagram of an embodiment of the present invention.

In the coating removing apparatus 21 of FIG. 1, a feed screw type vertical linear actuator 23 is vertically attached to the upper surface of a vertical support portion 22 having a U-shaped side surface, and a vertical feed screw 23a moves up and down. .. Lead screw 23a
Of the vertical guide 24 provided on the vertical support portion 22.
Is abutted on the upper surface of the hook-shaped forceps 25 that vertically moves up and down. Then, the spring 26 is vertically attached between the vertical support portion 22 and the forceps 25.

The tip of the forceps 25 has two fixing portions 25a,
25b (25b is not shown in the figure) Fixing parts 25a, 25b
The fitting part 25 for fixing one of the twin wires 27 to
a ₁ and 25b ₁ (25b ₁ not shown in the figure) are formed.

Then, the laser beam 28 is applied to the midpoint of one of the covered wires 27a of the twin wire 27, which is located between the fixed portions 25a and 25b and whose covering has been removed. In addition,
The twin wire 28 is gripped and moved by a gripping means (described in FIG. 2) in the axial direction of the twin wire 27 above a pad (solder is attached) 32 on the printed circuit board 31 for bonding. In this case, the pad 32 of the printed board 31 is a bonder (not shown) that moves up and down.
It is located directly below.

On the other hand, the lower portion of the vertical support portion 22 is attached so as to be movable in the horizontal direction by a horizontal guide 34 formed on an "L" -shaped horizontal support portion 33. Horizontal support 33
A horizontal linear actuator 35 is attached to the front end of the horizontal feed screw 35a that moves horizontally, and
Abut. Then, the vertical support portion 22 and the horizontal support portion 3
A spring 36 is attached between the three, whereby the horizontal support portion 22 moves horizontally.

An air cylinder 37 is attached to the lower portion of the horizontal support portion 33, and the air cylinder 37 is attached.
A shield plate 39, which is a shield member, is attached to the front end of the connector via a connecting member 38. The shield plate 39 can be moved in the arrow direction by the air cylinder 37, and the covered wire 2
7a and the printed circuit board 31.

In this case, the shielding plate 39 is positioned on the pad 32 when the coating is removed, and needs to be retracted when the wire 27a is positioned 0.1 mm above the printed circuit board 31 by the forceps 25. The position accuracy of about 1 mm is sufficient, and the air cylinder 3
7 is used.

Also, these vertical linear actuators 2
3, the horizontal linear actuator 35, and the air cylinder 37 are drive-controlled by the control unit 40.

Such a coating removing device 21 has a forceps 25.
Is moved in the vertical and horizontal directions by the vertical niria actuator 23 and the horizontal linear actuator 35, and the coated wire 27a (the wire portion from which the coating is removed) is positionally fixed on the pad 32 of the printed board 31.

Next, FIG. 2 shows a diagram for explaining the coating removal of FIG. First, in FIG. 2A, a bonder iron 41 is located above the pad 32 of the printed board 31. The twin wire 27 is grasped by the first hand 42 which is one end grasping means, pulled out to a predetermined position by the supplying means (not shown) (moving mechanism is explained in FIG. 3), and grasped by the second hand 43. Then, the coated wire 27a to be stripped is separated. The first and second hands 42, 43 apply a certain amount of tension to the twin wire 27. In this case, the distance between the covered wire 27a and the printed board 31 is about 2 mm.

Subsequently, the shield plate 39 is provided above the pad 32 and below the covered wire 27a by the air cylinder 37.
To move. Then, the first and second hands 4
A laser beam 2 is placed at an intermediate position of the covered wire 27a between the No. 2 and 43.
Irradiate 8. The intermediate position is provided to prevent the bonding position from being displaced due to plastic deformation of the wire during coating removal and during bonding.

The coated wire 27 is removed by the laser beam 28 to a length of about 100 μm to expose the wire portion 27b. In this case, the shielding plate 39 allows the laser light 28
Is prevented from irradiating onto the printed circuit board 31. As a result, it is possible to prevent the insulating layer formed of polyimide or the like on the printed board 31 from being destroyed. Next, in FIG. 2B, the shield plate 39 is moved and retracted,
Both ends of the wire portion 27b are fixed (fitted to the fitting portions 25a ₁ and 25b ₁ ) by the fixing portions 25a and 25b of the forceps 25 and pressed to 1 mm above the printed circuit board 31. In this case, the first
And by the second hands 42, 43, the wire portion 27b
The final minute position adjustment is performed (described in FIG. 3). Then, the wire portion 27b is bonded to the pad 32 by the bonder iron 41.

Next, FIG. 3 shows a configuration diagram when the position adjustment in FIG. 1 is performed. In FIG. 3, the first hand 4
2 is attached to the force sensor 41a, and the force sensor 51a is moved by the motor 52a in the axial direction of the covered wire 27a via the ball screw 53a. Also, similarly,
The second hand 43 is attached to the force sensor 51b, and the force sensor 51b is moved in the circumferential direction by the motor 52b via the ball screw 53b.

On the other hand, the signal from the force sensor 51a is input to the conversion unit 55a for converting the force deviation into the velocity via the input switching device 54. Further, the signal from the force sensor 51b is input to the input switching device 54, and the conversion unit 5
5b is input.

The controller 5 is provided in the conversion units 55a and 55b.
The target value (force detected by the force sensors 51a and 51b) is input from 6 and the control amounts are output from the conversion units 55a and 55b to the servo control amplifiers 57a and 57b. Then, the servo control amplifiers 57a and 57b cause the motor 5 to
2a, 52b to control the first and second hands 42,
43, and by extension, the wire portion 27b of the covered wire 27a is slightly moved.

That is, the force sensor 51 controls the difference between the target value of the force and the measured value as a velocity and controls it.
Both forces are controlled by the signal of a (or 51b), and when the force is smaller than the target value, the first and second hands 42, 43 are moved in the direction to pull the wire 27a to both sides, and the force is greater than the target value. When it is large, the first and second hands 42 and 43 are moved inward to weaken the tension of the wire 27a. With such force control, the center point between the first and second hands 42 and 43 does not always change regardless of the deformation of the wire 27a. Therefore, the removed wire portion 27b at the center of both hands 42 and 43 is not displaced by the plastic deformation of the wire 27a.

In this way, the removal of the coating at the bonding position where the position adjustment is easy is performed by using the laser beam for the printed circuit board 3
It is possible to prevent the destruction of the first insulating layer, and it is possible to prevent the printed circuit board from being damaged by the bonding work.

[0033]

As described above, according to the present invention, when the coating is removed by irradiating light near the bonding position, it is possible to move the shielding member between the coated wire and the substrate and near the bonding position. By locating, it is possible to prevent the insulating layer of the substrate from being broken by the laser light and prevent the substrate from being damaged.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an embodiment of the present invention.

FIG. 2 is a diagram for explaining the coating removal of FIG.

FIG. 3 is a configuration diagram when the position adjustment in FIG. 1 is performed.

FIG. 4 is a diagram for explaining conventional coating removal.

[Explanation of symbols]

21 coating removal apparatus 23 vertically linear actuators 23a vertical feed screw 25 forceps 25a, 25b fixed portion 25a _1, 25b ₁ fitting portion 27 twin wire 27a coated wire 28 laser beam 31 PCB 32 pads 35 horizontal linear actuator 35a horizontal feed screw 37 Air cylinder 39 Shielding plate 41 Bonding iron 42 First hand 43 Second hand

Claims (2)

[Claims] 1. When the two adherent coated wires (27) are bonded onto a substrate (31), the adhered coating gripped and supplied by gripping means (42, 43). The wire (27) is separated and one of the coated wires (2
A coating removing device for irradiating light (28) to 7a) to remove the coating, when the coating wire (27a) to be removed is irradiated with the light (28) in the vicinity of the bonding position. A coating removing device characterized in that a movable shield member (39) is located between the coating wire (27a) and the substrate (31) and near the bonding position. 2. A step of gripping one end by gripping means (42, 43) and pulling out the two closely adhered coated wires (27) from a supply means to a predetermined position on the substrate (31), and separating the covered wires (27). A step of moving the shielding member (39) above the bonding position of the substrate (31) and below the coated wire (27b), and near one of the separated bonding positions of the coated wire (27a). And a step of removing the coating by irradiating the surface with light (28), and a step of moving the shielding member (39) from the bonding position after the coating removal.