YV180X_Ope_E.pdf - 第263页
6 -28 EPD8013110 Operation Chapter 6 6 Using various functions 6 3. 4-point fiducial function The “ 4-point fiducial ” function is used to enhance the mounting position accuracy b y recognizing 4 fiducial marks pro vided…
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EPD8013110
Operation
Chapter 6
6
Using various functions
5.2 Local fiducial functions
There are three kinds of local fiducial functions relating to mount data:
“point fiducial”, “local fiducial” and “4-point fiducial” functions. These are
generally called the local fiducial functions.
The local fiducial functions are used to enhance the local mounting posi-
tion accuracy of individual mount data, rather than improving the mounting
position accuracy on an entire PCB or block as is done by the PCB fiducial
or block fiducial function. (See the preceding section, “5.1”.)
The local fiducial settings are specified on the following information
screens.
• Local fiducial mark coordinates: Local Fidu. Info.
• Mount data to use local fiducial function: Mount Info.
• Setting to use or not use local fiducial function: PCB Info.
1. Point fiducial function
The point fiducial function is used to enhance the mounting position
accuracy only of a specific component. In general, as the PCB size
becomes larger, the land pattern layout tends to become inaccurate due
to flexing, twist and expansion/shrinking of the PCB. Therefore, the
point fiducial function is effective when mounting QFP components
with a fine lead pitch on a large PCB. (Note that the PCB and block
fiducial functions are not effective in this case, although they are useful
in correcting a positioning error caused by the PCB clamping fluctua-
tions.)
The point fiducial function uses a set of two fiducial marks diagonally
located across the land patterns on which you want to improve mounting
position accuracy. It is okay if these two marks are different in shape,
but use the same marks for the same type of component.
2. Local fiducial function
The local fiducial function improves the mounting position accuracy of
two or more components within a specified area, by using a pair of
fiducial marks. This function is also effective in correcting the mounting
position errors when two or more different types of PCBs are supplied
on the same transfer pallet. The local fiducial marks must be arranged
diagonally across the specified area, but can be different in shape from
each other.
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EPD8013110
Operation
Chapter 6
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Using various functions
6
3. 4-point fiducial function
The “4-point fiducial” function is used to enhance the mounting position
accuracy by recognizing 4 fiducial marks provided on a PCB. This
function is effective in the following cases.
• PCBs with 4 or more fiducial marks which meet the conditions
• Large PCBs
• PCBs made of materials which tend to expand, flex or warp. (paper
phenol, paper, glass epoxy, other flexible materials)
The 4-point fiducial data settings are basically the same as those for
point fiducial and local fiducial marks. However, because the 4-point
fiducial function requires 4 XY coordinate points, you must use two data
lines on the Local Fidu. Info. screen in order to register one set of 4-
point fiducial marks.
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EPD8013110
Operation
Chapter 6
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Using various functions
5.2.1 Point fiducial and local fiducial functions
c
CAUTION
The following procedure for setting the fiducial function is explained, assuming that
you already have the complete PCB data needed for component mount. If you are not
yet finished with creating the PCB data, complete the PCB data first while referring to
Chapter 5 in this manual and then set the fiducial function.
1 Create the mark information.
On the Mark Info. screen you must first create the local fiducial mark data
to be used. When the two fiducial marks are identical, register the data for
just one mark. If they are different from each other, register the data
according to each mark. (Refer to “4. Creating the mark information” in
Chapter 5.)
2 Open the Local Fidu. Info. screen and set the fiducial
information.
Press the [F3] key in the <2/1/EDIT_DATA> mode to display the edit item
menu box. Select “Local Fidu. Info.” from the menu box and press the
[ENTER] key. On the Local Fidu. Info. screen, specify the fiducial informa-
tion as follows.
Mark : Enter the mark No. registered as the first mark
in the mark information.
X1, Y1 : For the point fiducial mark, enter the coordi-
nates of the first mark relative to the center of
the mounting position in millimeters. For the
local fiducial mark, enter the coordinates of
the first mark relative to the PCB origin (or the
block repeat No.1 point in the case of block
repeat reference) in millimeters.
Mrk2 : Enter the mark No. registered as the second
mark in the mark information. When the
second mark is identical with the first mark,
enter “0” here.)
X2, Y2 : For the point fiducial mark, enter the coordi-
nates of the second mark relative to the center
of the mounting position in millimeters. For
the local fiducial mark, enter the coordinates
of the second mark relative to the PCB origin
(or the block repeat No.1 point in the case of
block repeat reference) in millimeters.
Type : Set to “Point” for the point fiducial mark. Set
to “Local” for the local fiducial mark.
Skip : Set to “Exec” (initial setting) for both the point
and local fiducial marks.
Comment : You can enter a comment here as necessary.
This does not affect the data setting.