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User Manual S-23 HM 1 Introduction Software Version SR.405.xx 05/99 Issue 1.14 Overview of the modul es - vision systems 43 1.14 Overv iew of the modules - vision systems Each pl acement s ystem ha s 1 – two compo nent v…

1 Introduction User Manual S-23 HM

1.13 Overview of the modules - revolver head Software Version SR.405.xx 05/99 Issue

All the components are inserted with the same cycle time. Before the component is inserted, it is

measured by the optoelectronic vision system. 1

– The component vision camera creates an image of the current component.

– The precise position of the component is also determined.

– The package form of the current component is compared against the programmed package

form in order to identify it. Any components that cannot be identified are rejected.

– The turning station turns the component to the required placement position.

1.13.2 Description of the 12-segment revolver head

– The 12-segment revolver head works using the "collect & place" principle, i.e. the components

are held by the nozzles with the aid of a vacuum and, after one complete pick-up cycle, are

placed gently and accurately on the PCB with the aid of forced air. The vacuum in the nozzles

is also checked several times to determine whether the components were picked up and set

down correctly.

– The "adaptive" sensor stop mode of the z axis compensates for any irregularity of the PCB sur-

face when the components are set down.

– Defective components are rejected and are picked up again during a repair run.

1.13.3 Technical data - revolver placement head

Range of components

0402 to PLCC44, including BGA, µBGA, flip-chip,

TSOP, QFP, PLCC, SO to SO32, DRAM

Maximum height 6 mm

Minimum lead pitch 0.5 mm

Minimum dimensions 0.5 mm x 1.0 mm

Maximum dimensions 18.7 mm x 18.7 mm

Maximum weight 2 g

Maximum travel of the z axis 16 mm

Programmable set-down force 2.4 to 5.0 N

Nozzle types 9xx

Angular accuracy 0.7° at 4 sigma

Placement accuracy ± 90 µm at 4 sigma

± 67.5 µm at 3 sigma

User Manual S-23 HM 1 Introduction

Software Version SR.405.xx 05/99 Issue 1.14 Overview of the modules - vision systems

1.14 Overview of the modules - vision systems

Each placement system has 1

– two component vision cameras on the placement heads and

– two PCB vision cameras on the underside of the x axis gantries.

The vision analysis unit is located in the control unit for the placement system and the component

vision system is used to determine: 1

– the precise position of the components at the nozzle and

– the geometry of the package form.

The PCB vision system uses fiducials on the PCBs to determine: 1

– the position of the PCB,

– its rotation angle

– and the PCB delay.

The PCB vision system also uses fiducials on the feeder modules to determine the exact pick-up

position of components, which is particularly important for small components. 1

1.14.1 Technical data - component vision module on the 12-segment revolver head

Maximum component dimensions 18.7 mm x 18.7 mm

Range of components 0402 to PLCC44

including BGA, µBGA, flip-chip, TSOP, QFP

PLCC, SO to SO32, DRAM

Lead spacing > = 0.5 mm

Field of vision 24 mm x 24 mm

Illumination method Front-lighting (3 levels programmable as required)

1 Introduction User Manual S-23 HM

1.14 Overview of the modules - vision systems Software Version SR.405.xx 05/99 Issue

1.14.2 Technical data - PCB vision system

Fiducials Up to 3 per placement program

Local fiducials Up to 2 per component (may be of different types)

Library size Up to 255 fiducial types - system fiducials

≥

249

Image processing Gray scale-based correlation

Illumination method Front-lighting

Recognition time per fiducial/ink spot 0.4 s

Field of vision 5.7 mm x 5.7 mm