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TECHNIC AL RE FERENCE MECHANICAL DETAIL 1.16 ProFlow Manual Chapter Issue 8 Dec 02 NOTE For ease of i dentifica tion, all tr ansfer heads wi th single condi tioning c hambers are coloured black and al l transfer heads wi…

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TECHNICAL REFERENCE
MECHANICAL DETAIL
Chapter Issue 8 Dec 02 ProFlow Manual 1.15
Conditioning
Chamber
The ProFlow transfer head contains a conditioning chamber for maintaining the
condition of the print material. This chamber can be accessed by removing the
primary grid, which is accessible whilst the carrier unit is in the open position.
The grid is sealed onto the conditioning chamber by means of two M4 counter-
sunk screws and ‘O’ ring which fits into the transfer head (ProFlow Transfer
Head Figure refers). There are two types of conditioning chamber for both the
cassette carrier unit and rechargeable unit, as follows:
• Single Conditioning Chamber
• Dual Conditioning Chamber
Single Conditioning
Chamber
The single conditioning chamber, ensures maximum print material optimization
on conventional SMT PCBs printing, the printing material is driven around the
conditioning chamber and bottom chamber by the action of the adhesive nature
of the printing material to the stencil, while the transfer head traverses the
image.
Dual Conditioning
Chamber
The dual conditioning chamber, was partly developed from knowledge gained
with the single conditioning chamber. This ensures maximum print material
transfer and optimization on more demanding process platforms, the print
material is driven around the two individual side chambers, in the same manner
as above.
Transfer
Head
Stencil
BoardWiper
ProFlow Movement (Y Axis)
Piston
Crosshead
Print Material
Conditioning Chamber
Secondary Grid
Primary
Grid
Transfer
Head
Stencil
BoardWiper
Piston
Crosshead
Side Chambers
Nozzle
ProFlow Movement (Y Axis)
Print Material
TECHNICAL REFERENCE
MECHANICAL DETAIL
1.16 ProFlow Manual Chapter Issue 8 Dec 02
NOTE
For ease of identification, all transfer heads with single conditioning chambers
are coloured black and all transfer heads with dual conditioning chambers are
coloured blue.
Cassette Carrier The cassette carrier unit is attached to the conditioning chamber by a hinged
bracket, this is swung open when fitting the cassette into place (ProFlow
Transfer Head figure refers).
The cassette is located within the carrier by means of integral ribs and two
retaining pins.
NOTE
When loading a cassette, before the carrier is swung back onto the conditioning
chamber, the cassette sealing strip must be removed.
Two clamp brackets at each end of the transfer head are latched over the carrier
and cassette, these are secured by tightening the thumbscrews into the carrier
dimples.
The cover is fitted to the underside of the ProFlow transfer head during periods
when the ProFlow unit is not in use. This seals any exposed printing material
from the atmosphere and also prevents inadvertent seepage or spills onto the
stencil.
Cassette The 300mm ProFlow cassette capacity is between 800g and 850g of solder
paste.
WARNING
SOLDER PASTE AND SOLVENTS. WHEN USING OR HANDLING ANY SOLDER
PASTE OR SOLVENT FORMULATION THE MANUFACTURERS’ RECOMMEND
SAFETY PRECAUTIONS MUST BE STRICTLY ADHERED TO.
WARNING
PROTECTIVE CLOTHING. APPROVED PROTECTIVE CLOTHING SHOULD BE
WORN BY SOLDER PASTE AND SOLVENT HANDLERS AT ALL TIMES TO
ELIMINATE FUME INHALATION, EYE CONTACT, SKIN CONTACT AND
INGESTION.
Figure 1-10 Cassette Overview
TECHNICAL REFERENCE
MECHANICAL DETAIL
Chapter Issue 8 Dec 02 ProFlow Manual 1.17
The specially designed ProFlow cassette makes loading of the print material
rapid and user friendly. The cassette system reduces waste to an absolute
minimum and is also environmentally friendly (the operator does not have to
touch or manually work print material at any stage during print operations).
The routine for changing cassettes is detailed in the Consumable Replenish-
ments chapter of the machine manual.
ProFlow cassettes are supplied hermetically sealed with a tear off foil, this is
removed after the cassette has been fitted to the ProFlow transfer head. If the
cassette is being fitted to a new or cleaned transfer head, ie where the transfer
head conditioning chamber is free from print material. The ProFlow unit should
be primed as detailed in the Consumable Replenishments chapter of the
machine manual before print operations are carried out.
When the cassette is fitted to the ProFlow unit the system is totally enclosed,
maintaining the print material in optimum condition. If the system has not been
used for some time a knead operation is available, as detailed in the Sequences
- Knead Paste section of this chapter.
A cover can be fitted to the underside of the transfer head during periods when
the ProFlow unit is in the raised position or if the transfer head is removed.
Figure 1-11 ProFlow Cassette
Semco Cassette
Retaining Pin Recesses
Cassette Shown with Sealing Strip Removed