User-Manual-NeoDen3V-PNP-machine.pdf - 第40页
35 3.2.4. Maintenance of Device Routine che ck an d mainte nance policy sho uld be esta blished. 3.2.4.1. Check Belo w Poin ts Da ily Inspection Items Please check b elow before turn on the machine 1) T emperature and hu…
34
3.2. Maintenance
3.2.1. Reinforce Daily Maintenance
P&P machine is a relatively complex, high-tech and high-accuracy device that requires a extremely clean working
environment with constant temperature and humidity. Thus, it’s must to be strictly in accordance with regulations
of the equipment to have a routine maintenance.
3.2.2. Requirement for Operator
Operator should get the basic training which covers all the skills and knowledge needed to safely operate this
type of pick and place machine.
Operating strictly against equipment’s instruction. DON’T use machine with problems. Stop the machine
once malfunction appears and contact with the after-sales service staff, restart to work after problem solved.
Operator should be concentrated during the process.
Observation—to observe whether there is abnormal situation. For example peel-box can’t work, plastic tape
is broken etc.
Listening—to hear whether strange sounds appears during operation, such as noise of placement head, sound
of loss component, strange noise of conveyor etc.
Handwork—solve small problems in time, such as install feeder, correction placement position etc. If
anything wrong with the main machine body or circuit, please consult after-sales staff.
3.2.3. Formulate Measures to Reduce/ Avoid Mistake
The most easily appeared problem during mounting are components placement incorrectly and placement
misaligned. Refer to below measures for precaution.
1) It needs to check whether the components’ package is matched with related feeder. If not, please correct
them.
2) As for tape reel feeder, after one is ran out, operator must check whether another newly changed tape reel is
correct or not.
3) After import the SMD file or edit chip list manually, please recheck each component’s No., nozzle’s rotation
angle and placement position to ensure they’re correct.
4) Operator must check the first finished PCB of each file. If any problem happens, please find solutions such as
revise program to solve it.
5) Check placement position’s alignment, component loss problem during regular work from time to time. Find
the reason in time and come up with solutions.
6) Detect position before soldering(manually or using AOI)
7) To sum up, P&P machine’s running speed and placement accuracy still has limitations. Human plays an
important role in running well of the machine. So it’s necessary to comply with effective measures to ensure
machine’s well working, high placement quality and efficiency.
35
3.2.4. Maintenance of Device
Routine check and maintenance policy should be established.
3.2.4.1. Check Below Points Daily
Inspection Items
Please check below
before turn on the
machine
1) Temperature and humidity: temperature range from 20℃ to 26℃, humidity
range from 45% to 70％.
2) No stuff on dual rails or the whole placement area.
3) No stuff on the fix camera lens. Make it clean and tidy.
4) No stuff around the head nozzles.
5) Check if nozzle is dirty or out of shape. Clean it or change it into a new one.
6) No stuff on the feeders, and make sure they’re well installed.
7) Check if the air hose is well connected with the machine.
Please check below
after turn on the
machine
1) Check if the monitor’s screen could display well after system starting working.
2) Check if emergency switch could work well.
3) Check if the placement head could return to the original place correctly.
4) Check if noise happens when placement head moving.
5) Check if negative pressure could under a normal range.
6) Check the PCB’s transmission on dual rails to see if the sensor still works
well.
7) Check the positioning column and holes are correct and fastened.
3.2.4.2. Check Below Points Monthly
Checking Points
Checking List
X、Y axis
Make sure no abnormal noise when placement head move.
X、Y motor
Make sure motors working well, no abnormal heating appearance.
Nozzle
Check if nozzles stretch well with no bending and check if the suction surface is
horizontal.
Air hose
Check the air hose and connector, make sure hose is fine without broken, abrasion or
air-leak etc.
Step Motor
Make sure no dust on the step motor, synchronous belt and synchronous wheel; the Z
axis motor can rotate and fluctuate without obstacles.
Z axis Motor
Check if the placement head could move up and down smoothly. Push up the nozzle by
hand to see whether it can move smoothly. Move the placement head up and down in
the proper range.
Negative pressure
check all nozzles’ negative pressure.If abnormal,please clean nozzles.
Positive pressure
check whether they’re normal.
Optical axis
please check whether it is covered dusk. Please keep it clean and lubricated.
Operation button
check each button to make sure they are well-worked
Connector
check if well-connected of the air connector and air hose.
36
3.2.5. Related Issues During Solder Paste Printing Process
3.2.5.1. Stencil Printer Technology
Screen printing technology refer to using ready-made stencil, directly contact to the printer in a certain way, make
the solder paste evenly flow on the stencil and then leak into the mesh through the holes. When getting the stencil
away, solder paste had been covered to the printed circuit board solder graphics corresponding, thus complete the
solder paste printing on the PCB.
3.2.5.2. Inspecting of Solder Paste Printing
Printing process is one of the key working procedure to ensure the quality of surface mounting. According to the
statistics,under the premise of guaranteed quality about components and PCB,correctly PCB design, 70% of the
surface quality problem caused during printing process. In order to ensure the quality of SMT assembly, it is
necessary to strictly control the quality of the solder paste printing.
The amount of solder paste printing requirements are as follows:
The using amount of solder paste should be uniform, good consistency. Solder paste graphics should be clear,
try to avoid adhesion between adjacent graphics. Solder paste graphics and solder graphics should be
consistent.
In general,keep unit area amount of solder paste about 0.8 mg/mm². For fine pitch components, should be 0.5
mg/mm² (using stencil thickness and hole size to control in the actual operation).
Printed on the substrate of solder paste compared with required value, a certain deviation is permissible, the
covering area of the solder paste on each solder pad should be more than 75%.
Should be no seriously collapsing problem and edges neatly after solder paste had been printed, the
dislocation shouldn’t be larger than 0.2 mm, for solder pad of fine pitch components,dislocation shouldn’t be
larger than 0.1MM,pollution by solder paste is not permitted to the PCB.