Specification_SIPLACE_S23HM_eng - 第18页

17 Target Low Structure Correlati on Description With the SIPLAC E S-23 HM, se v- eral vision modules with a ce ntral vision system to anal yze recorde d image data ensure high placement precision. At one of the machine’…

Description

When a batch change occurs, the

changeover tables can be set up

and checked at the external

SIPLACE set-up station quickly and

without machine idle time. The

costs for production of a vast

number of variants are greatly re-

duced. When a bar code check is

conducted outside the machine,

10 minutes of machine idle time

are eliminated per set-up change.

Access to all current set-up data

from as many as 4 lines exists via

a link to a Local Area Network

(LAN) for the line computer.

Two component changeover ta-

bles belong to the standard

equipment of an SIPLACE

S-23 HM. Additional component

changeover tables are required for

optimal use of the set-up station.

Component Supply:

External SIPLACE Set-Up Station (Option)

Example for SIPLACE Set-Up Station

PC for External

Set-Up

LAN Scanner

Serial Interface

Line Computer

Line

LAN

Accessories

Operating system Windows NT 4.0

Set-up check Using bar code scanner

Time required:

Component table change 2 min / table side

Tape Reel

with

Bar Code

Changeover

Table

Component Changeover Tables

Target Low

Structure Correlation

Description

With the SIPLACE S-23 HM, sev-

eral vision modules with a central

vision system to analyze recorded

image data ensure high placement

precision.

At one of the machine’s two X-

gantries the PCB vision module

recognizes offsets in the position

of the PCB in the conveyor sys-

tem. The modules are also re-

quired to scan the machine or the

feeders on one side of the table.

Each vision module consists of a

CCD camera with integrated light-

ing and optics.

The offsets in PCB position are de-

termined with the help of at least

two - but generally three - refer-

ence marks on the PCB. When the

PCB arrives, the gantry with its

PCB vision module moves to the

programmed mark position. The

vision system compares the re-

corded video image with the sam-

ple stored in the PCB description.

By applying the correlation princi-

ple the vision system can deter-

mine the correct position through

comparisons with programmed

target structures even when refer-

ence marks are incomplete or

damaged (actual structures).

The shapes are not inviolably

specified; they can be taught with-

out restrictions.

Additional functions of the PCB vi-

sion module are the position rec-

ognition of the feeders and ce-

ramic substrates (optional) and the

calculation of processing data in-

cluding mapping.

In addition, recognition of faulty

PCBs is conducted via ”ink spots”

with the aid of the PCB vision

module.

Vision Sensor Technology:

PCB Vision Module

Technical Data

Reference marks

Local marks

Library memory

Recognition of poor panels

up to 3 (subpanels and multiple panels)

up to 2 per component

(may be of different type)

up to 255 types of reference marks

per subpanel

Image analysis Correlation principle

based on gray-scale values

Lighting method Front lighting

Recognition time

mark/ink spot

0.8 s

Camera’s field of view 5.7 x 5.7 mm

Correlation Principle

Actual High

Structure Correlation

Description

Different reference mark shapes

prove to be optimal depending on

the condition of the surface.

Particularly advisable for bare cop-

per surfaces with little oxidation is

the single cross. Maximum recog-

nition reliability is achieved due to

the high information content. Rec-

tangle, square and circle are less

”informative” but save space, are

rugged, and can even be used

when oxidation is at an advanced

stage.

Advisable for tinned structures are

circle or square because in this

case the ratio of the mark dimen-

sions to the presolder thickness is

particularly favorable.

Vision Sensor Technology:

PCB Position Recognition

Template

Window

PCB Camera

Field of View

Area

Fiducial to

Be Located

Reference

Fiducal

Reference Mark Criteria

Locate 2 marks

Locate 3 marks in addition

X-/Y-position, rotation angle, mean dis-

tortion

Shear, distortion in X- and Y-direction

Mark shapes Freely definable via teaching, e.g.,

single cross, rectangle, square, circle

Mark surface

Copper

Tin

Without oxidation and solder resist

Warp ≤ 1/10 of structure width,

good contrast to environment

Mark dimensions

single cross

rectangle/square

circle

Length and width: 0.9 - 2 mm

Line thickness: 0.3 - 1.0 mm

Edge length: 0.5 - 2 mm

Diameter: 0.5 - 2 mm

Mark environment Clearance around reference mark not

necessary if there is no similar mark

structure in the search area

(5.7 x 5.7 mm)