Information
-
Patent Grant
-
6592065
-
Patent Number
6,592,065
-
Date Filed
Thursday, October 11, 200123 years ago
-
Date Issued
Tuesday, July 15, 200321 years ago
-
Inventors
-
Original Assignees
-
Examiners
Agents
- Varndell & Varndell, PLLC
-
CPC
-
US Classifications
Field of Search
US
- 242 4173
- 242 333
- 242 353
- 242 3522
- 242 357
- 242 5342
- 242 5353
- 242 538
- 242 5382
-
International Classifications
-
Abstract
A winding type flexible printed circuit board tape transferring system includes tape let-off wheel unit, a tape take-up wheel unit, two idle wheel units adapted to guide movement of the flexible printed circuit board tape from the tape let-off wheel unit to the tape take-up wheel unit, a tension control wheel unit adapted to control the tension of the flexible printed circuit board tape being transferred from the tape let-off wheel unit to the tape take-up wheel unit, and at least one work wheel unit adapted to rotate a respective rotary encoder upon movement of the flexible printed circuit board tape, enabling the rotary encoder to output a signal to a control unit indicative of the position of the flexible printed circuit board tape.
Description
BACKGROUND AND SUMMARY OF THE INVENTION
The present invention relates to a printed circuit board tape transferring system, and more specifically, to winding type flexible printed circuit board tape transferring system, which is practical to transfer flexible printed circuit board of different types and widths.
Following fast development of telecommunication industry, semiconductor industry, and planer display industry, different thin-film tapes such as tape carried package, tape ball grid array, and chip on film are intensively used as tapes for printed circuit board. These flexible film tapes commonly have sprocket holes symmetrically arranged along the two opposite lateral sides for positioning in a transferring system. The thickness of these flexible film tapes is about 0.025˜0.125 mm. The width of these flexible film tapes ranges from minimum 35 mm to maximum over 200 mm. When employing these flexible film tapes to the fabrication of flexible printed circuit board, several problems may be encountered as outlined hereinafter.
1. It is difficult to keep the coplanarity of the flexible film tape without any contacts at the region of circuits during the manufacturing process.
2. When transferring the flexible film tape, an improper control of the transmission mechanism may cause the transmission mechanism to damage or deform the sprocket holes of the flexible film tape.
3. A flexible film tape without sprocket holes is not transferable.
4. When running an examination operation, the transferring system must be break off, and then the examination apparatus is operated to examine one segment of the flexible film tape, and then the flexible film tape is carried forwards, and then the examination apparatus is returned to its former position for examining a next segment of the flexible film tape. This repeated transferring and examining procedure wastes much time.
The present invention has been accomplished to provide a winding type flexible printed circuit board tape transferring system, which eliminates the aforesaid drawbacks. It is one object of the present invention to provide a winding type flexible printed circuit board tape transferring system, which is practical to transfer flexible printed circuit board tapes of different widths. It is another object of the present invention to provide a winding type flexible printed circuit board tape transferring system, which is practical to transfer flexible printed circuit board tape having sprocket holes as well as flexible printed circuit board tapes without sprocket holes. It is still another object of the present invention to provide a winding type flexible printed circuit board tape transferring system, which keeps the flexible printed circuit board tape flattened transversely extended out when transferring it, preventing the flexible printed circuit board tape from wrinkling. According to one aspect of the present invention, the winding type flexible printed circuit board tape transferring system includes a tape let-off wheel unit controlled to let off a flexible printed circuit board tape for processing, a tape take-up wheel unit controlled to take up the flexible printed circuit board tape from the tape let-off wheel unit, two idle wheel units adapted to guide movement of the flexible printed circuit board tape from the tape let-off wheel unit to the tape take-up wheel unit, a tension control wheel unit adapted to control the tension of the flexible printed circuit board tape being transferred from the tape let-off wheel unit to the tape take-up wheel unit, and at least one work wheel unit adapted to rotate a respective rotary encoder upon movement of the flexible printed circuit board tape, enabling the rotary encoder to output a signal to a control unit indicative of the position of the flexible printed circuit board tape. According to another aspect of the present invention, the wheels of the tension control wheel unit, idle wheel units, and at least one work wheel unit each comprise a wheel axle, a fixed wheel blade fixedly fastened to the wheel axle, an adjustment wheel blade slidably mounted on the wheel axle in parallel to the fixed wheel blade and fixed in the desired position subject to the width of the flexible printed circuit board tape by a holding down screw. The fixed wheel blade and the adjustment wheel blade each have a shoulder adapted to support the flexible printed circuit board tape being transferred from the tape let-off wheel to the take-up wheel.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1
is a perspective view of a winding type flexible printed circuit board tape transferring system according to the present invention.
FIG. 2
is an exploded view in an enlarged scale of a part of the present invention, showing the arrangement of the tape let-off wheel unit and the tape take-up wheel unit on the rack.
FIG. 3
is an exploded view in an enlarged scale of a part of the present invention, showing the arrangement of the tension control wheel unit on the rack.
FIG. 4
is an exploded view in an enlarged scale of a part of the present invention, showing the arrangement of the work wheel unit on the rack.
FIG. 5
is an exploded view in an enlarged scale of a part of the present invention, showing the arrangement of the idle wheel unit on the rack.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to
FIG. 1
, a winding type flexible printed circuit board tape transferring system in accordance with the present invention is shown comprised of a tape let-off unit
1
, two idle wheel units
5
, a tension control wheel unit
3
, at least one, for example, two work wheel unit
4
, a tape take-up wheel unit
2
, and a rack
6
.
Referring to FIG.
5
and
FIG. 1
again, the idle wheel units
5
are mounted on the rack
6
near two opposite lateral sides and adapted to guide the flexible film tape
7
from the let-off wheel
10
to the take-up wheel
20
, each comprised of an axle bearing
53
, a wheel axle
54
, and an idle wheel
50
. The axle bearing
53
is fixedly fastened to the rack
6
by fastening elements, for example, screws
52
, having one side
531
extended through the rack
6
. The wheel axle
54
is supported in the corresponding axle bearing
53
, having one side
542
coupled to the corresponding idle wheel
50
.
Referring to FIG.
2
and
FIG. 1
again, the tape let-off unit
1
comprises a motor
11
, a coupling
12
, an axle bearing
13
, a wheel axle
14
, and a let-off wheel
10
. The motor
11
has an output shaft
111
adapted to rotate the wheel axle
14
and the let-off wheel
10
, causing the let-off wheel
10
to let off the flexible film tape
7
, and a power line
112
connected to the frequency transformer of the control unit (not shown), which controls the speed of the motor
11
. The axle bearing
13
is fixedly fastened to the rack
6
by fastening elements, for example, screws
15
. The wheel axle
14
has one end
141
inserted through the axle bearing
13
and then coupled to the output shaft
111
of the motor
11
by the coupling
12
, and the other end
142
fastened to the let-off wheel
10
.
Referring to FIG.
3
and
FIG. 1
again, the tension control wheel unit
3
comprises a linear motor
31
, a vertical track
32
, an axle bearing
33
, a wheel axle
34
, and a tension wheel
30
. The linear motor
31
is adapted to move the axle bearing
33
and the wheel axle
34
along the vertical track
32
to the desired elevation, causing the tension wheel
30
to control the tension of the flexible film tape
7
being delivered from the let-off wheel
10
to the take-up wheel
20
. The position signal of the linear motor
31
is provided to the control unit for reference, enabling the control unit to control the speed of the tape let-off unit
1
and the tape take-up unit
2
properly. The linear motor
31
is fixedly fastened to the rack
6
by fastening elements, for example, screws
35
. The vertical track
32
comprises two parallel rails
321
fixedly fastened to the rack
6
along two long sides of the longitudinal sliding slot
61
in the rack
6
by fastening elements, for example, screws
36
, and two slides
322
respectively slidably coupled to the rails
321
. The axle bearing
33
is fixedly fastened to the slides
322
by fastening elements, for example, screws
37
, having a rear side
331
inserted through the longitudinal sliding slot
61
of the rack
6
and coupled to the reciprocating shaft
311
of the linear motor
31
. The wheel axle
34
has one end
342
coupled to the axle bearing
33
, and the other end
341
coupled to the tension wheel
30
. When starting the motor
31
to move the reciprocating shaft
311
forwards (upwards) or backwards (downwards), the axle bearing
33
is moved with the reciprocating shaft
311
upwards or downwards along the longitudinal sliding slot
61
, and therefore the tension wheel
30
and the wheel axle
34
are moved with the axle bearing
33
to adjust the tension of the flexible film tape
7
.
Referring to FIG.
4
and
FIG. 1
again, each work wheel unit
4
comprises a work wheel
40
, a coupling
42
, an axle bearing
43
, a wheel axle
44
, and a rotary encoder
41
. The flexible film tape
7
is extended from the let-off wheel
10
through the idle wheel
50
of one idle wheel unit
5
, the tension wheel
30
, the work wheel
40
of each work wheel unit
4
, and the idle wheel
50
of the other idle wheel unit
5
to the take-up wheel
20
. During forward movement of the flexible film tape
7
, the friction force between the flexible film tape
7
and the work wheel
40
forces the work wheel
40
to rotate, thereby causing the rotary encoder
41
to rotate with the work wheel
40
. The rotary encoder
41
detects the position of the flexible film tape
7
, and provides a corresponding signal to the control unit for further examination and circuit exposure control. The axle bearing
43
is fixedly fastened to the rack
6
by fastening means, for example, screws
45
. The wheel axle
44
has one end
441
inserted through the axle bearing
43
and coupled to the wheel shaft
411
of the rotary encoder
41
by the coupling
42
, and the other end
442
fastened to the work wheel
40
. The wheel shaft
411
of the rotary encoder
41
is inserted through an opening
471
of a bracket
47
at the rack
6
, and coupled to the wheel axle
44
by the coupling
42
.
Referring to
FIGS. 1 and 2
, the tape take-up wheel unit
2
comprises a motor
21
, a coupling
22
, an axle bearing
23
, a wheel axle
24
, and a take-up wheel
20
. The motor
21
has an output shaft
211
adapted to rotate the wheel axle
24
and the take-up wheel
20
, causing the take-up wheel
20
to take up the flexible film tape
7
from the let-off wheel
10
and a power line
212
connected to the frequency transformer of the control unit, which controls the speed of the motor
21
subject to the speed of the motor
11
of the tape let-off unit
1
. The axle bearing
23
is fixedly fastened to the rack
6
by fastening elements, for example, screws
25
. The wheel axle
24
has one end
241
inserted through the axle bearing
23
and then coupled to the output shaft
211
of the motor
21
by the coupling
22
, and the other end
242
fastened to the take-up wheel
20
.
During operation, the idle wheel
50
of each idle wheel unit s guides the flexible film tape
7
from the let-off wheel
10
to the take-up wheel
20
, and the tension wheel
30
controls the tension of the flexible film tape
7
. When the flexible film tape
7
passing over the shoulder
401
of the work wheel
40
of each work wheel unit
4
, the work wheel
40
is forced to rotate, thereby causing the corresponding rotary encoder
41
to rotate synchronously, so that the rotary encoder
41
accurately detect the amount of movement of the flexible film tape
7
and provides a signal indicative of the position of the flexible film tape
7
to the control unit for further examining, scanning, and circuit exposure controls. Further, the shoulder
401
of the work wheel
40
of each work wheel unit
4
forces the flexible film tape
7
to extend out in transverse direction, preventing the flexible film tape
7
from wrinkling.
Further, the idle wheel
50
of each idle wheel unit
5
, the tension wheel
30
of the tension control wheel unit
3
, and the work wheel
40
of each work wheel unit
4
are respectively comprised of a fixed wheel blade
502
,
302
or
402
and an adjustment wheel blade
503
,
303
or
403
. The fixed wheel blade
502
,
302
or
402
and the adjustment wheel blade
503
,
303
or
403
each have a wheel shoulder
501
,
301
or
401
and a wheel hub
500
,
300
or
400
. The wheel shoulders
501
,
301
or
401
support the flexible film tape
7
, keeping the middle part of the flexible film tape
7
suspended above the wheel hubs
500
,
300
or
400
. Therefore, the wheels
50
,
30
, and
40
do not touch the circuit area
71
of the flexible film tape
7
during movement of the flexible film tape
7
from the let-off wheel
10
to the take-up wheel
20
. The fixed wheel blade
502
,
302
or
402
is fixedly fastened to the respective wheel axle
54
,
34
, or
44
. The adjustment wheel blade
503
,
303
or
403
is mounted on the respective wheel axle
54
,
34
, or
44
and fixed in position by a tightening up screw
505
,
305
, or
405
. When loosened the tightening up screw
505
,
305
, or
405
, the adjustment wheel blade
503
,
303
or
403
can be moved axially along the respective wheel axle
54
,
34
, or
44
to adjust the pitch between the fixed wheel blade
502
,
302
or
402
and the adjustment wheel blade
503
,
303
or
403
subject to the width of the flexible film tape
7
to be delivered.
As indicated above, the invention achieves the following advantages:
1. When delivering the flexible film tape
7
from the let-off wheel
10
to the take-up wheel
20
, the shoulders
501
,
301
, and
401
of the wheels
50
,
30
, and
40
force the flexible film tape
7
to extend out in transverse direction, preventing the flexible film tape
7
from wrinkling.
2. The transferring system is practical to transfer a flexible film tape, which is partially wrinkled or deformed.
3. The wheels
3
,
4
, and
5
are so designed that the pitch between the respective fixed wheel blade
302
,
402
or
502
and the adjustment wheel blade
303
,
403
, and
503
is adjustable subject to the width of the flexible film tape to be transferred.
4. The transferring system is practical to transfer flexible film tapes having sprocket holes as well as flexible film tapes without sprocket holes.
A prototype of winding type flexible printed circuit board tape transferring system has been constructed with the features of FIGS.
1
˜
5
. The winding type flexible printed circuit board tape transferring system functions smoothly to provide all of the features discussed earlier.
Although a particular embodiment of the invention has been described in detail for purposes of illustration, various modifications and enhancements may be made without departing from the spirit and scope of the invention. Accordingly, the invention is not to be limited except as by the appended claims.
Claims
- 1. A winding type flexible printed circuit board tape transferring system comprising:a rack; a tape let-off wheel unit mounted on said rack, said tape let-off wheel unit comprising a let-off wheel controlled to let off a flexible printed circuit board tape; a tape take-up wheel unit mounted on said rack, said tape take-up wheel unit comprising a take-up wheel controlled to take up the flexible printed circuit board tape from said tape let-off wheel unit; two idle wheel units respectively mounted on said rack, said idle wheel units each comprising an idle wheel adapted to guide movement of the flexible printed circuit board tape from said tape let-off wheel unit toward said tape take-up wheel unit; a tension control wheel unit mounted on said rack and arranged between said idle wheel units, said tension control wheel unit comprising a tension wheel- moved to control the tension of the flexible printed circuit board tape being transferred from said tape let-off wheel unit toward said tape take-up wheel unit; and at least one work wheel unit mounted on said rack and arranged between said idle wheel units, said at least one work wheel unit each comprising a work wheel disposed in contact with the flexible printed circuit board tape being transferred from said tape let-off wheel unit toward said tape take-up wheel unit and forced to rotate upon movement of the flexible printed circuit board tape, and a rotary encoder coupled to said work wheel for synchronous rotation with said work wheel to detect the position of the flexible printed circuit board tape being transferred from said tape let-off wheel unit toward said tape take-up wheel unit and to output a signal to a control unit indicative of the position of the flexible printed circuit board tape.
- 2. The winding type flexible printed circuit board tape transferring system as claimed in claim 1 wherein the idle wheel, tension wheel, and work wheel of each of said idle wheel units, said tension control wheel unit, and each of said at least one work wheel unit each comprise a wheel axle, a fixed wheel blade fixedly fastened to said wheel axle, an adjustment wheel blade mounted on said wheel axle and axially slidably arranged on said wheel axle in parallel to said fixed wheel blade, and a holding down screw adapted to fix said adjustment wheel blade to said wheel axle to fix the pitch between said fixed wheel blade and said adjustment wheel blade, said fixed wheel blade and said adjustment wheel blade each having a shoulder adapted to support the flexible printed circuit board tape being transferred from said let-off wheel to said take-up wheel.
- 3. The winding type flexible printed circuit board tape transferring system as claimed in claim 2 wherein:said tape let-off wheel unit further comprises a motor fixedly mounted on said rack and controlled to rotate said let-off wheel, the motor of said tape let-off wheel unit comprising an output shaft, a wheel axle fixedly fastened to said let off wheel, an axle bearing fixedly mounted on said rack and adapted to support the wheel axle being fixedly fastened to said let-off wheel, and a coupling, which couples the wheel axle at said let-off wheel to the output shaft of the motor of said tape let-off wheel unit for enabling motor of said tape let-off wheel unit to rotate said let-off wheel; said tape take-up wheel unit further comprises a motor fixedly mounted on said rack and controlled to rotate said take-up wheel, the motor of said tape take-up wheel unit comprising an output shaft, a wheel axle fixedly fastened to said take-up wheel, an axle bearing fixedly mounted on said rack and adapted to support the wheel axle being fixedly fastened to said take-up wheel, and a coupling, which couples the wheel axle at said take-up wheel to the output shaft of the motor of said tape take-up wheel unit for enabling motor of said tape take-up wheel unit to rotate said take-up wheel; said idle wheel units each further comprise an axle bearing fixedly mounted on said rack and adapted to support the wheel axle of the respective idle wheel unit for enabling the idle wheel of the respective idle wheel unit to be rotated upon movement of the flexible printed circuit board tape from said let-off wheel toward said take-up wheel; said tension control wheel unit further comprises a linear motor fixedly mounted on said rack and adapted to move said tension wheel vertically, said linear motor comprising a vertically extended reciprocating shaft, a vertical track fixedly mounted on said rack, and an axle bearing supporting the wheel axle of said tension wheel on said track and moved with said reciprocating shaft along said vertical track to control the elevational position of said tension wheel; said at least one work wheel unit each further comprises an axle bearing fixedly mounted on said rack and adapted to support the wheel axle of the work wheel of the respective work wheel unit, and a coupling, which couples the axle wheel of the work wheel of the respective work wheel unit to the rotary encoder of the respective work wheel unit for enabling the work wheel of the respective work wheel unit to rotate the rotary encoder of the respective work wheel unit upon movement of the flexible printed circuit board tape from said let-off wheel toward said take-up wheel.
US Referenced Citations (6)