JP2797877B2 - Strip conveyor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a strip transporting apparatus, and more particularly to a strip transporting apparatus for performing laser marking, bonding, and the like on a device while transporting a lead frame or the like on which a semiconductor element is mounted.

[0002]

2. Description of the Related Art In the manufacture of semiconductor devices, for example, when performing laser marking or bonding on a semiconductor element mounted on a lead frame, a predetermined operation is performed while the lead frame is being conveyed. The operation related to the marking operation will be described below with reference to FIG. In the drawing, (1) is a lead frame on which a semiconductor element is mounted, (2) is a vertically movable and open / close movable grip portion for gripping a rear end of the lead frame (1),
(3) is a timing belt for setting and holding the grip portion (2), and (4) and (4) are pulleys around which the timing belt (3) is wound and whose shaft is connected to a motor (not shown). , (5) are laser markers arranged at predetermined positions on the timing belt (3).

In the above configuration, the rear end of one lead frame (1) is gripped by the grip portion (2), conveyed to the laser marker side by the timing belt (4), and mounted immediately below the laser marker (5). Each time an element arrives, laser marking is sequentially performed on the element. When all the markings on one lead frame (1) are completed, the lead frame (1) is removed, and the pulley (4) is rotated in the reverse direction to return the grip portion (2) to the initial position. And the marking operation are repeated.

[0004]

The problem to be solved is that every time a predetermined operation such as laser marking is completed, the timing belt (3) is reversed to return the grip portion (2) to the initial position once. Therefore, during the return time, the work is temporarily interrupted, resulting in a loss time, and the productivity is reduced. Also, timing belts (4) and (4)
Therefore, there is also a problem that the conveying speed varies, the positional accuracy decreases, the marking position varies, and the marking character arrangement is irregularly disturbed.

[0005]

According to the present invention, a pair of first and second grip portions for gripping the respective rear end portions of two strip-shaped strips, and the first and second grip portions are provided. A pair of first and second holding portions for holding up and down freely, and a pair of being arranged in parallel,
A servo drive type in which the first and second holding portions are independently screwed, each grip portion is reciprocated in the same vertical plane, and two strips are simultaneously conveyed in a fixed direction while maintaining a constant interval. First,
And a second ball screw,

Further, each position of the first and second grips is detected, and each servo of the first and second ball screws is maintained so that the distance between the first and second grips always keeps a minimum constant interval corresponding to the length of the strip-shaped strip. A control unit for controlling driving is provided, and the speed of each grip unit is controlled, and the control unit transmits data for work processing including at least a strip length and the number of strip mounted elements. It is characterized by having.

[0007]

According to the above technical means, the rear ends of two strip frames such as a lead frame are respectively gripped by the first and second grip portions, and the grip portions are fixed in the same vertical plane in the same vertical plane. And one of the grips or the strip that it is holding is the other
It will not interfere with the grip part of the
As described above, the sheet is continuously conveyed while maintaining the minimum constant interval according to the length of the strip . Each time the preceding grip reaches the work position, the work is performed on the strip, and when the work is completed, the work is continuously performed on the rear grip. And ball screw feed is by timing belt
High accuracy compared to feeding.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a strip conveying apparatus according to the present invention will be described below with reference to FIGS. First, FIG. 1 and FIG. 2 show a schematic plan view and a side view of a strip transport device (6) according to the present invention. In the figure, (7a) and (7b) are the first and second grip portions, (8a) and (8b) are the first and second holding portions, and (9)
a) (9b) is first and second ball screws, and (10) is a control unit. The first and second grip portions (7a) (7b)
Is openable and closable, and grips the respective rear end portions of the strip-shaped strips (11a) (11b) such as a lead frame as in the prior art. First,
The second holding portions (8a) and (8b) hold the first and second grip portions (7a) and (7b) vertically movable. The first and second ball screws (9a) and (9b) are connected in parallel to the servomotors (12a) and (12b), respectively, and the first and second holding portions (8a) and (8b) are independent of each other. Screwed on. And each grip part (7a) (7
b) is reciprocated in the same vertical plane (P), and the two strips (11a) and (11b) are simultaneously conveyed in a fixed direction while maintaining a constant interval. The control unit (10) is equipped with a computer and has data for work processing such as the length of the strip, the number of mounted elements on the strip and, in the case of marking, the number of prints and the like, and the servo motors (12a) (12b). ), The positions and speeds of the grip portions (7a) and (7b) are detected by calculation from the rotation speed and speed. Therefore, for example, the first grip portion (7
The position detection data of a) is sent to the second grip portion (7b), and the band between the two is always held by the rear grip portion.
Set the minimum fixed interval as short as possible without hitting the grip
Each grip part (7a) to hold according to the length of
(7b) is speed-controlled or numerically controlled.

The operation of the present invention based on the above configuration will now be described. First, the rear end of the band plate (11a) is gripped by the first grip portion (7a), and the rear end portion of the band plate (11b) is fixed to the second grip portion (7b) at a fixed interval behind the first grip portion (7a). And further, as shown in FIG. 2, each of the strips (11a) (1
The height of the second grip portion (7b) is set slightly lower than the first grip portion (7a) so that 1b) does not collide. Therefore, the first ball screw (9a) is servo-rotated by the servo motor (12a) to rotate the first grip portion (7).
a) is conveyed at a predetermined speed with high precision to the work position side (left direction in the figure) such as laser marking. At the same time, the second ball screw (9b) is servo-rotated to hold the second grip portion (7b) rearward from the first grip portion (7a) with a minimum fixed interval with high precision, and the work position side (left direction in the figure). At a predetermined speed.

Therefore, each time the strip (11a) reaches the work position, a predetermined work such as laser marking is performed on the mounted element and the like thereon. And the strip (11
When the operation of a) is completed, predetermined operations such as laser marking are continuously performed on the strip (11b) gripped by the second grip portion (7b). At the same time, the first grip portion (7a) is immediately returned to the initial position by rotating the servo motor (12a) in the reverse direction, and the same operation is repeated. At this time,
The servo motor (12a) (12
From the number of rotations and speed of b), each grip part (7a) (7b)
The position and the speed of the grip (7a) (7
When the operation is interrupted when b) returns to the initial position, the servo motors (12a) and (12b) are reversely rotated at the highest speed to minimize the operation loss time. Similarly, the positions of the first and second grip portions (7a) and (7b) are detected from the rotational speeds and speeds of the servo motors (12a) and (12b) to control the grip portions (7a) and (7b). ), Speed control and numerical control are performed, for example, the second grip portion (7b) is moved so as to always maintain the minimum constant interval with respect to the preceding first grip portion (7a). This is achieved high precision and high speed of work significantly can reduce the work loss time, was able to reduce the working time.

Next, referring to FIG. 3 and FIG. 4, the general structure of the strip conveying apparatus according to the present invention will be described below.
(7b) is first and second grip portions, (8a) and (8b) are first and second holding portions, and (9a) and (9b) are first and second ball screws. The first and second grip portions (7a) (7
b), as shown in FIG. 3, the strip guides (13a) (1)
In the gap corresponding to the strip width (W) of 3b), the first,
Slide part (14a) of the second holding part (8a) (8b)
(14b) so as to be vertically movable and, as shown in FIG. 4, each pair of vertically movable gripping pieces (T
a) (Tb). Then, gripping pieces (T) are attached to both ends of the rod (15) that rotates the seesaw around the fulcrum (B).
a) While connecting the lower ends of (Tb), the rod (1)
One end of 5) is urged downward by a tension spring (R).

Further, the slide portions (14a) (14b) are held by external upper and lower two-stage cylinders (16), and the cylinders (1) are held.
When the two stages of 6) are simultaneously projected or retracted, the slide portions (14a) (14b) and the gripping pieces (Ta) (Tb) are raised or lowered while being opened, and only the upper stage of the cylinder (16) is retracted. Then, the holding pieces (Ta) and (Tb) are closed. Then, after the gripping pieces (Ta) and (Tb) are raised while being opened, only the upper stage of the cylinder (16) is retracted, and the gripping pieces (T
a) Close (Tb) and grasp the end of the strip. Also, the first,
The first and second holding portions (8a) and (8b) are screwed on the second ball screws (9a) and (9b), and the band plate is guided (13a).
The sheet is conveyed in a fixed direction by servo rotation while being guided by (13b).

[0013]

According to the present invention, the strip-shaped strips are gripped by the two grip portions one by one and continuously transported in a state where the minimum fixed interval is maintained. it is so arranged perform predetermined work, can achieve a working high speed, operation time and productivity is significantly reduced is greatly improved. I
We use a ball screw for the feed, so positioning can be performed with high accuracy
Wear.

[Brief description of the drawings]

FIG. 1 is a schematic plan view showing an embodiment of a strip conveying apparatus according to the present invention.

FIG. 2 is a schematic side view showing an embodiment of the strip conveying apparatus according to the present invention.

FIG. 3 is a front view showing a general configuration of the strip transport device according to the present invention.

FIG. 4 is a partial side view showing a general configuration of the strip transport device according to the present invention.

FIG. 5 is a schematic side view showing an example of a conventional strip transport device.

[Explanation of symbols]

 7a 1st grip part 7b 2nd grip part 8a 1st holding part 8b 2nd holding part 9a 1st ball screw 9b 2nd ball screw 10 control part 11a strip 11b strip

Claims (3)

(57) [Claims] 1. A pair of first and second grips for gripping a rear end of a strip-shaped strip, and a pair of first and second grips for holding the first and second grips so as to be vertically movable. The first and second holding portions are independently screwed, and each grip portion is reciprocally driven in the same vertical plane to hold the strip-shaped strip at a constant interval. A belt transport device comprising: servo-driven first and second ball screws for transporting in a fixed direction in a state. 2. Each of the first and second ball screw servos so as to detect the respective positions of the first and second grip portions and to always maintain a minimum constant interval according to the length of the strip-shaped strip. 2. The strip conveying apparatus according to claim 1, further comprising a control unit for controlling driving, wherein the speed of each grip unit is controlled. 3. The work unit including at least a strip length.
Strip conveying apparatus according to claim 2, characterized in that it has data for management.