1. A method for printing a solder mask on a printed circuit board (PCB), the method comprises:
acquiring images of multiple areas of a PCB by an inspection unit while the PCB is supported by a mechanical stage;
determining spatial differences between a model of the PCB and the PCB based on the images;
determining solder mask ink deposition locations based on (i) the spatial differences, and (ii) locations of the model of the PCB that should be coated with the solder mask ink; and
printing solder mask ink on the solder mask deposition locations by a printing unit, while the PCB is supported by the mechanical stage.
2. The method according to claim 1, further comprising:
determining whether the PCB is of at least a desired quality, based on at least some of the images; and
printing solder mask ink only if the PCB is of at least the desired quality.
3. The method according to claim 1, comprising:
inspecting the PCB after a completion of the printing of the solder mask ink to detect missing solder mask ink locations that should have been coated by solder mask ink but are not coated by solder mask ink, while the PCB is supported by the mechanical stage; and
printing solder mask ink on at the missing solder mask ink locations while the PCB is supported by the mechanical stage.
4. The method according to claim 1, comprising: inspecting the actual PCB after depositing solder mask ink at a plurality of solder mask ink deposition locations to detect missing solder mask ink locations that should have been coated by solder mask ink but are not coated by solder mask ink, while the PCB is supported by the mechanical stage; and printing solder mask ink on at the missing solder mask ink locations while the PCB is supported by the mechanical stage
5. The method according to claim 1, comprising:
inspecting the PCB after a after depositing solder mask ink at a plurality of solder mask deposition locations to detect excess solder mask ink; and
removing the excess solder mask ink by a repair unit.
6. The method according to claim 1, wherein the models of the PCB is a computer aided design models of the PCB.
7. The method according to claim 1, comprising:
acquiring images of multiple areas of the PCB by an inspection unit while introducing movement between the inspection unit and a bridge that is located above the mechanical stage; and
printing solder mask ink on the solder mask deposition locations by the printing unit while introducing movement between the printing unit and the bridge.
8. The method according to claim 1, comprising:
acquiring images of multiple areas of the PCB by an inspection unit while introducing movement between the inspection unit and a first bridge that is located above the mechanical stage; and
printing solder mask ink on the solder mask deposition locations by the printing unit while introducing movement between the printing unit and a second bridge.
9. The method according to claim 1, comprising:
acquiring images of multiple areas of the PCB by an inspection unit while moving the mechanical stage along a first direction and moving the inspection unit along a second direction; and
printing solder mask ink on the solder mask deposition locations while moving the mechanical stage along a first direction and moving the printing unit along a second direction.
10. The method according to claim 1 comprising curing the solder mask ink by the printing unit.
11. The method according to claim 1 wherein the determining of the spatial differences comprising performing global alignment and local alignment.
12. A system for solder mask printing on a printed circuit board (PCB), the system comprises:
a mechanical stage for supporting the PCB;
an inspection unit for acquiring images of multiple areas of a PCB while the PCB is supported by the mechanical stage;
a processor for determining spatial differences between a model of the PCB and the PCB based on the images and for determining solder mask ink deposition locations based on (i) the spatial differences, and (ii) locations of the model of the PCB that should be coated with the solder mask ink; and
a printing unit for printing solder mask ink on the solder mask deposition locations, while the PCB is supported by the mechanical stage.
13. The system according to claim 12, wherein the processor is configured to determine whether the PCB is of at least a desired quality, based on at least some of the images and wherein the printing unit is arranged to print solder mask ink only if the PCB is of at least the desired quality.
14. The system according to claim 12, wherein the inspection unit is arranged to inspect the PCB after a completion of the printing of the solder mask ink to detect missing solder mask ink locations that should have been coated by solder mask ink but are not coated by solder mask ink, while the PCB is supported by the mechanical stage; and wherein the printing unit is arranged to print solder mask ink on at the missing solder mask ink locations while the PCB is supported by the mechanical stage.
15. The system according to claim 12, wherein the inspection unit is arranged to inspect the actual PCB after depositing solder mask ink at a plurality of solder mask ink deposition locations to detect missing solder mask ink locations that should have been coated by solder mask ink but are not coated by solder mask ink, while the PCB is supported by the mechanical stage; and wherein the printing unit is arranged to print solder mask ink on at the missing solder mask ink locations while the PCB is supported by the mechanical stage.
16. The system according to claim 12, wherein the inspection unit is arranged to inspect the PCB after a after depositing solder mask ink at a plurality of solder mask deposition locations to detect excess solder mask ink; and wherein the system further comprises a repair unit for removing the excess solder mask ink.
17. The system according to claim 12, wherein the model of the PCB is a computer aided design model of the PCB.
18. The system according to claim 12, wherein the inspection unit is arranged to acquire images of multiple areas of the PCB by an inspection unit while introducing movement between the inspection unit and a bridge that is located above the mechanical stage; and wherein the printing unit is arranged to print solder mask ink on the solder mask deposition locations by the printing unit while introducing movement between the printing unit and the bridge.
19. The system according to claim 12, wherein the inspection unit is arranged to acquire images of multiple areas of the PCB by an inspection unit while introducing movement between the inspection unit and a first bridge that is located above the mechanical stage; and wherein the printing unit is arranged to print solder mask ink on the solder mask deposition locations by the printing unit while introducing movement between the printing unit a second bridge.
20. The system according to claim 12, wherein the inspection unit is arranged to acquire images of multiple areas of the PCB by an inspection unit while moving the mechanical stage along a first direction and moving the inspection unit along a second direction; and wherein the printing unit is arranged to printing solder mask ink on the solder mask deposition locations while moving the mechanical stage along a first direction and moving the printing unit along a second direction.
21. The system according to claim 12 wherein the printing unit is arranged to cure the solder mask ink by the printing unit.
22. The system according to claim 12 wherein the processor is arranged to determine the spatial differences comprising performing global alignment and local alignment.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A tandem image forming device comprising:
a plurality of image forming sections arranged side by side on an incline and each comprising a developing device and a cleaning device arranged around an image carrier; and
one of nearby ones of said plurality of image forming sections having said cleaning device thereof positioned overhanging a part of said developing device of other image forming sections.
2. A method of arranging a plurality of image forming sections, each of which comprises a developing device and a cleaning device arranged around an image carrier, comprising:
arranging the plurality of image forming sections side by side in a tandem image forming device on an incline; and
positioning the cleaning device overhanging a part of the developing device of other image forming sections in one of nearby ones of said plurality of image forming sections.
3. An image forming apparatus comprising:
an intermediate image transfer body implemented as an inclined belt;
process cartridges arranged along the intermediate image transfer body;
each of said process cartridges having a developing device and a cleaning device;
said developing device arranged above said cleaning device; and
a fixing device arranged in a space of the image forming apparatus beneath the inclination of the belt.
4. The apparatus as claimed in claim 3, wherein said fixing device comprises an endless belt and is configured to fix a toner image formed on a recording medium.
5. The apparatus as claimed in claim 3, wherein said inclined belt comprises an elastic layer and a smooth coating layer covering a surface of said elastic layer.
6. The apparatus as claimed in claim 5, wherein said elastic layer is not flexible in a circumferential direction of said intermediate image transfer body, but is elastic at at least a surface thereof and subjected to a pressure by secondary transfer.
7. The apparatus as claimed in claim 3, wherein said developing device comprises an agitating section and a developing section,
said agitating section being positioned at a lower level than the developing section with said cleaning device overlying said agitating section.
8. The apparatus as claimed in claim 3, wherein said cleaning device comprises a cleaning blade and a fur brush.
9. The apparatus as claimed in claim 8, wherein said cleaning device further comprises an electric field roller configured to apply a bias to said fur brush.
10. The apparatus as claimed in claim 3, further comprising:
a plurality of image forming sections distributed along the inclined belt.
11. The apparatus as claimed in claim 10, wherein said image forming sections each further comprises a primary image transfer device, a charger, and a drum.
12. The apparatus as claimed in claim 3, further comprising:
a controller configured to output an emergency stop command when an error occurs.
13. The apparatus as claimed in claim 3, further comprising:
a sensor located on a sheet conveyance path and configured to sense a leading edge of a recording medium; and
a registration roller pair preceding an image transfer position configured to correct a skew of the recording medium.
14. The apparatus as claimed in claim 3, further comprising:
a sensor located on a sheet conveyance path and configured to sense a leading edge of a recording medium fed by a feeding operation, which occurs at a preselected interval; and
a registration roller pair preceding an image transfer position and configured to correct a skew of the recording medium.
15. The apparatus as claimed in claim 3, further comprising:
a turning device configured to turn a recording medium in order to form a toner image on both sides of said recording medium.
16. An image forming apparatus comprising:
a transfer body implemented as an inclined belt;
a fixing device arranged in a space of the image forming apparatus beneath the inclination of the belt;
process cartridges arranged along the transfer body;
each of said process cartridges having a developing device and a cleaning device; and
said developing device arranged above said cleaning device.