00193407-02 HWWS SIPLACE Machine Accuracy EN.pdf - 第17页
© Siemens AG . . Änderungen vorbehalten SIPLACE Placement Systems = 1,33 37.5 um (50 - 0) um limit value - offset = = cmk 3 Sigma x -4 σ -50 -37.5 -25 -12.5 0 12.5 25 37.5 +50 limit value +- 50 um Sigma = 12.5 um 1. Proc…
© Siemens AG . . Änderungen vorbehalten
SIPLACE
Placement Systems
C
mk
>1,33
C
mk
<1,33
C
mk
<1,33
dispersion low,
Sigma < 12.5 um,
offset too high,
process is not centered
dispersion low,
Sigma < 12.5 um,
offset too high,
process is not centered
dispersion low,
Sigma < 12.5 um,
no offset,
process is centered
example: specification 50 um at 4 Sigma (1 sigma = 12.5 um)
Machine Capability
© Siemens AG . . Änderungen vorbehalten
SIPLACE
Placement Systems
=
1,33
37.5 um
(50 - 0) umlimit value - offset
=
=
cmk
3 Sigma
x
-4σ
-50 -37.5
-25 -12.5
0
12.5
25
37.5
+50
limit value +- 50 um
Sigma = 12.5 um
1. Process is centered, no offset
calculation after placing components
Sigma = 10 um,
offset = 0, process is centered
limit value +- 50 um
-40
-30
-20
-10
0
20
30
40
10
=
1,66
30 um
(50 - 0) um
=
limit value - offset
3 Sigma
=
cmk
example: specification 50 um at 4 Sigma
+4σ
-1σ
+
1σ
x
-4σ
+
4σ
-50
+50
Maschinenfähigkeit
© Siemens AG . . Änderungen vorbehalten
SIPLACE
Placement Systems
limit value +- 50 um
-40
-30
-20
-8
0
-50
20
30
40
50
10
um
Offset -8 um
Calculation after placing components
Sigma = 10 um,
Offset = -8, Process is not
centered,
but in specification (>1.33)
=
1,4
30 um
(50 - 8) umlimit value - offset
=
=
cmk
3 Sigma
limit value +- 50 um
-40
-28
-20
-10
0
-50
20
30
40
50
10
um
Offset
-28 um
=
0,73
30 um
(50 - 28) um
=
limit value - offset
3 Sigma
=
cmk
Calculation after placing components:
Sigma = 10 um,
Offset = -28, Process is not centered
and not
in specification (<1.33)
2. Process is centered, small offset
3. Process is centered, big offset
x
-4σ
+
4σ
-1σ+1σ
x
-4σ
+
4σ
-1σ
+
1σ
Maschinenfähigkeit
example: specification 50 um at 4 Sigma