The finishing system is one of the most valuable productivity features of a Konica Minolta bizhub multifunction printer. While the print engine creates the image on paper, the finisher is responsible for organizing, sorting, stapling, punching, folding, booklet making, and delivering the completed documents.
Understanding how the finisher and output devices operate helps technicians diagnose paper jams, misaligned staples, incomplete booklets, and communication errors between the main engine and the finishing unit. This guide explains every major component, how paper travels through the finisher, and the most common service issues encountered in the field.
What Is a Finisher?
A finisher is an external paper handling module attached to the side of the bizhub machine. It receives printed sheets from the printer engine and performs finishing operations before placing the paper into an output tray.
Depending on the model, a finisher can perform:
- Multi-position stapling
- Corner stapling
- Saddle stitching
- Booklet making
- Folding
- Hole punching
- Offset sorting
- Job separation
- Large-capacity stacking
Without a finisher, printed pages simply exit into the standard output tray.
Main Finisher Components
A Konica Minolta finisher contains numerous electromechanical assemblies.
1. Entrance Rollers
These rollers receive paper from the printer.
Functions:
- Pull sheets into the finisher
- Maintain proper paper timing
- Prevent skew
- Deliver sheets to transport rollers
Common failures:
- Worn rubber
- Dirt buildup
- Roller slipping
Symptoms:
- Entrance jams
- Skewed pages
- Delayed paper arrival
2. Transport Rollers
Transport rollers move paper through the entire finisher.
Their job includes:
- Maintaining constant speed
- Keeping sheet alignment
- Feeding paper toward each finishing station
Transport rollers work together with:
- Timing sensors
- Drive gears
- Transport belts
3. Paper Guides
Paper guides direct sheets through different finishing paths.
Depending on the selected job, guides send paper toward:
- Output tray
- Stapler
- Punch unit
- Folding unit
- Saddle stitch section
Most guides are controlled by:
- Solenoids
- Small DC motors
- Springs
4. Exit Rollers
Exit rollers deliver completed documents to the output tray.
They maintain:
- Correct sheet spacing
- Output speed
- Proper stacking
Finisher Control Board
Every finisher contains its own control PCB.
Its responsibilities include:
- Motor control
- Sensor monitoring
- Stapler communication
- Punch operation
- Error detection
- Position feedback
The main printer communicates with the finisher through dedicated connectors.
If communication fails, the machine may display:
- Finisher communication errors
- Optional device not detected
- Initialization failures
Finisher Motors
Modern finishers contain several motors.
Examples include:
- Main transport motor
- Stapler motor
- Punch motor
- Shift tray motor
- Elevator motor
- Folding motor
- Saddle stitch motor
Each motor is monitored by:
- Home sensors
- Rotation sensors
- Encoder feedback
If a motor fails to rotate correctly, the machine immediately stops operation.
Sensors Inside the Finisher
Sensors continuously monitor paper movement.
Common sensors include:
- Entrance sensor
- Registration sensor
- Punch sensor
- Staple position sensor
- Exit sensor
- Tray full sensor
- Tray lift sensor
- Booklet sensor
Sensors detect:
- Paper arrival
- Paper departure
- Tray position
- Jam locations
- Finished document position
Dirty sensors are among the most common causes of false paper jams.
Output Trays
Most bizhub finishers include multiple output trays.
These trays may include:
- Main tray
- Sub tray
- Booklet tray
- Shift tray
Each tray is monitored by sensors that detect:
- Full tray
- Tray position
- Elevator height
Shift Tray Operation
One popular finishing feature is offset stacking.
Instead of placing every job in the same position, the shift tray moves slightly left or right after each print job.
Benefits:
- Easy job separation
- Faster document organization
- No separator sheets required
The movement is controlled by:
- Shift motor
- Home position sensor
- Rack-and-pinion mechanism
Stapling System
The stapling unit automatically staples finished document sets.
Major components include:
- Staple cartridge
- Staple driver
- Staple clincher
- Staple motor
- Home sensor
Stapling Process
- Pages arrive.
- Sheets are aligned.
- The stapler moves into position.
- Staple is driven through paper.
- Clincher bends staple legs.
- Document exits.
Sheet Alignment System
Before stapling, sheets must be perfectly aligned.
The alignment mechanism uses:
- Jogging plates
- Side fences
- Alignment rollers
- Alignment motors
The system vibrates or shifts pages until every sheet is perfectly square.
Poor alignment causes:
- Crooked staples
- Staple jams
- Fold errors
Hole Punch Unit
Optional punch units create binder holes.
Available configurations include:
- 2-hole
- 3-hole
- 4-hole
- European hole patterns
The punch mechanism consists of:
- Punch pins
- Punch dies
- Punch motor
- Waste container
Paper chads are collected inside a removable waste box.
A full punch waste container often causes service warnings.
Folding Unit
Certain finishers include folding capability.
Common fold types:
- Half fold
- Letter fold
- Z-fold
- Double parallel fold
- Gate fold
Folding units use:
- Fold rollers
- Fold plates
- Timing sensors
- Folding motor
Incorrect fold timing usually causes:
- Wrinkled paper
- Fold jams
- Uneven folds
Saddle Stitch Booklet Maker
The saddle stitch unit produces professional booklets.
Operation sequence:
- Printed sheets are collected.
- Sheets are folded.
- Staples are inserted through the fold.
- Booklet is trimmed (model dependent).
- Finished booklet exits.
Common booklet sizes:
- A4 booklet
- Letter booklet
Elevator Tray System
High-capacity finishers include elevator trays.
As paper accumulates:
- Tray lowers automatically.
- Sensor monitors stack height.
- Elevator motor adjusts tray position.
This prevents paper from backing up into the exit rollers.
Paper Transport Sequence
The complete paper path is:
Printer Engine → Exit Rollers → Finisher Entrance → Transport Rollers → Selected Finishing Station → Output Rollers → Output Tray
Depending on the selected finishing option, the path changes automatically.
Examples:
No finishing:
Printer → Output Tray
Staple:
Printer → Alignment → Stapler → Tray
Punch:
Printer → Punch → Tray
Booklet:
Printer → Saddle Stitch → Fold → Booklet Tray
Communication Between the Printer and Finisher
Before each job begins, the printer sends finishing instructions.
Typical commands include:
- Staple location
- Number of copies
- Punch option
- Fold type
- Tray selection
- Offset stacking
The finisher confirms:
- Ready status
- Motor positions
- Sensor status
- Completion of each operation
If communication fails, printing may continue without finishing or stop entirely, depending on the model and configuration.
Common Finisher Problems
1. Paper Jam in Finisher
Possible causes:
- Dirty rollers
- Broken guides
- Sensor blockage
- Worn transport rollers
2. Staple Jam
Causes:
- Bent staple cartridge
- Worn driver
- Foreign object
- Misaligned stapler
3. No Staple
Possible causes:
- Empty cartridge
- Stapler motor failure
- Home sensor failure
- Driver mechanism jam
4. Crooked Staples
Usually caused by:
- Poor paper alignment
- Worn joggers
- Stapler position error
5. Punch Errors
Possible causes:
- Full waste box
- Broken punch pin
- Punch motor failure
- Incorrect paper size
6. Fold Errors
Common causes:
- Dirty fold rollers
- Worn rollers
- Incorrect paper weight
- Timing sensor failure
7. Tray Full Errors
Possible causes:
- Defective tray sensor
- Incorrect elevator position
- Full output tray
Preventive Maintenance
To ensure reliable operation:
- Clean transport rollers regularly.
- Remove paper dust from sensors.
- Empty punch waste containers.
- Inspect stapler cartridges.
- Lubricate moving mechanisms where specified in the service manual.
- Replace worn rollers during scheduled maintenance.
- Check transport belts for wear or damage.
- Verify finisher firmware compatibility after controller or engine updates.
Regular preventive maintenance greatly reduces jams, misfeeds, and finishing defects while extending the service life of the finisher.
Service Tips for Technicians
When troubleshooting a finisher:
- Verify the optional device is recognized by the machine.
- Run output device and finisher diagnostics in Service Mode.
- Check sensor status while manually feeding paper through the finisher.
- Inspect transport rollers for glazing or contamination.
- Test all motors individually if supported by the service mode.
- Examine gears, timing belts, and drive couplings for wear or broken teeth.
- Confirm connectors and harnesses between the printer engine and finisher are secure.
- Clear all paper scraps after a jam, especially around sensors and the stapling unit.
- Update firmware when recommended by Konica Minolta to resolve known finisher issues.
- Always perform a complete finishing test—including stapling, punching, folding, and booklet creation if installed—before returning the machine to the customer.
Conclusion
The Konica Minolta bizhub finisher is a sophisticated electromechanical system that transforms printed sheets into organized, professionally finished documents. Through the coordinated operation of transport rollers, sensors, motors, alignment mechanisms, staplers, punch units, folding assemblies, and output trays, the finisher automates tasks that would otherwise require significant manual effort.
For field technicians, understanding the complete paper path, the role of each component, and the interaction between the printer engine and the finisher is essential for diagnosing jams, communication faults, staple and punch errors, and output quality problems. Routine inspection, cleaning, and preventive maintenance not only minimize downtime but also ensure consistent finishing performance and longer equipment life.