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Asse mb ly In st ruct i on s 0100 5- Pac ket Edi t io n 12 /200 7 71 4.1. 2 (Error D etectio n (Fin e t uning) The f ollowing ac tions serv e as a che ck list fo r improvem ent of the p ickup rate a nd t he DPM rate. 4 V…

Assembly Instructions 01005-Packet

Edition 12/2007

4.1.1.3 Handling of Nozzles

– Replace nozzles only with nozzle changer

– Avoid touching the nozzles tips to prevent pollution

– Always use an ultrasonic bath to clean nozzles (Mat.# 03042652-01)

Note:

The small deviation of the ceramic nozzle tip poses the risk of injury (comparable with a pin).4

4.1.1.4 PCB upport

The PCB must be supported in such a way that it is not resilient and cannot arch up or down. In

the case of extremely thin substrates, holohedral support, where necessary, with the help of vac-

uum tooling is recommended. Ceramic substrates may require ceramic substrate centering. 4

4.1.1.5 Testing First Placement Run

In order to verify whether all settings have been prepared and set correctly, a trial placement run

onto a PCB imprinted with soldering paste is recommended. A trial placement run onto adhesive

foil does not yield any meaningful results, since the soldering paste imprint has a significant impact

on the placement quality. 4

Assembly Instructions 01005-Packet

Edition 12/2007

4.1.2 (Error Detection (Fine tuning)

The following actions serve as a check list for improvement of the pickup rate and the DPM rate.4

Various tests showed that a bad pickup rate affects the quality of the placement. If the components

rest highly excentric, flipped, tilted or reversed on the nozzle after pickup, the components might

shift out of place or may be inserted inaccurately when impinging onto the soldering paste storage.

That is primarely the case, when the vision system allows for this due to wrong component mea-

surements or too large tolerance entries in the component shape description. Hence it is important

to ensure that real component dimensions are used and that the entries for tolerance strike a sen-

sible balance between too many vision errors and a secure pickup. The values for component di-

mensions or pickup tolerances entered into the default component shapes should serve as

reference values. These might vary depending on the component manufacturer, the component

type or the quality criteria. Therefore it is possible that a component type produced by different

manufacturers requires the construction of different component shapes. 4

Vision errors can be analyzed subsequently in the "View" => "Vision Measurements" menu. This

allows for a quick assessment whether a damaged component, inferior component shape descrip-

tions or a flawed pickup process are the error cause. Distorted or partially fractured components

are a sign of defective components. Tolerance discrepancies in frame measurements are far more

frequent though. 4

Additionally, differences in brightness at the passivation layer with terminators can lead to face

down recognition errors. 4

The quality of the soldering paste print further determines the placement quality. The use of too

much soldering paste or lthe build up of lobe structure during the print process will influence the

placement accuracy. The use of dried-up or too little soldering paste corrupts the component grip

onto the PCB. This increases the danger of components being pulled-up by the nozzle after place-

ment. 4

Assembly Instructions 01005-Packet

Edition 12/2007

4.1.2.1 Error: Bad Error Rate

Components are placed flipped, upright or tilted at the nozzle when viewing the vision life image;

Components jump out of the component pocket or stick to the extracted tape foil during feeder

synchronizing. 4

– Causes at the feeder:

– Does the feeder synchronize with delay? > Remove extracted tape foil from feeder > Tape

must unroll smooth-running from tape reel!

– Is the pickup position or the pitch set correctly?

– Is the feeder cover cap closed properly?

– Is the discharged spacer available?

– Is the foil extraction clean?

– Is the correct feeder 00176100.xx in use?

– Is the tape placed onto the spacer or does it bounce?

– Does the feeder stay in pickup position during synchronizing?

(Verification suggestion: via LP camera in the ("Display setup" => "Correct position") menu.

Pickup position will be started up. If the feeder is synchronized repeatedly, the pickup posi-

tion must not move around).

– Causes at the machine:

– Is the feeder position recognition active?

– Has the component pocket not been recognized properly during feeder position recogni-

tion? (Verification suggestion: via LP camera in the (Display setup > Correct position menu).

If necessary, repeat the feeder position recognition with the component in the tape slot (Dis-

play setup > Feeder position recognition).

– Is the automatic compressed air switch off active? Reduce switch off time, if necessary.

– Are the nozzles soiled, worn out or put on the wrong way? Verification possibility through

individual functions (Gantry > <Nozzle offsets revolver head > new measurement).

– Replace all nozzles displayed as soiled or worn out with clean ones.

– For SIPLACE D4 only: Has the changeover table height been adjusted so that the feeder

position recognition will function reliably?