Konica Minolta DF-312 User Manual

SERVICE MANUAL

Model

DF-312

SEPTEMBER 1999

CSM-DF-312

KONICA BUSINESS TECHNOLOGIES, INC.

DF-312

SERVICE MANUAL

September 1999

Used on Model 7065

IMPORTANT NOTICE

Because of the possible hazards to an inexperienced person servicing this equipment, as well as the risk of damage to the equipment, Konica Business Technologies strongly recommends that all servicing be performed by Konica-trained service technicians only.

Changes may have been made to this equipment to improve its performance after this service manual was printed. Accordingly, Konica Business Technologies, Inc., makes no representations or warranties, either expressed or implied, that the information contained in this service manual is complete or accurate. It is understood that the user of this manual must assume all risks or personal injury and/or damage to the equipment while servicing the equipment for which this service manual is intended.

Corporate Publications Department

© 1999, KONICA BUSINESS TECHNOLOGIES, INC. All rights reserved.

Printed in U.S.A.

CONTENTS

CONTENTS
SAFETY PRECAUTIONS ................................................	V
DF-312
PRODUCT SPECIFICATIONS ..............................................	1
Type .............................................................................	1
Functions ........................................................................	1
Machine Data .................................................................	1
Maintenance ...................................................................	1
Operating Environment ..................................................	1
CENTER CROSS-SECTIONAL DRAWING ..........................	2
DRIVE SYSTEM DRAWING .................................................	2
ORIGINAL CONVEYANCE PROCESS .................................	3
Single side original copy mode ......................................	3
Double side original copy mode .....................................	4
Mixed original copy mode ...............................................	4
EXTERNAL SECTION ...........................................................	5
Composition ...................................................................	5
Mechanism .....................................................................	5
Disassembly and Reassembly .......................................	6
PAPER FEED/PAPER EXIT SECTION .................................	9
Composition ...................................................................	9
Mechanism .....................................................................	9
Disassembly and Reassembly .....................................	10
Paper feed/conveyance/scan control ...........................	12
Paper exit/reversal conveyance control .......................	14
Original size detection control ......................................	16

DIAGRAMS
ELECTRICAL PARTS LAYOUT DRAWING .......................	19
CONNECTOR LAYOUT DRAWING ...................................	20
OVERALL WIRING DIAGRAM ...........................................	21
TIMING CHART (8.5 X 11, ONE SIDE ORIGINALS, FIVE
SHEETS) ...........................................................................	22
TIMING CHART (8.5 X 11, DUAL-SIDED ORIGINALS,
TWO SHEETS) ..................................................................	22

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iv

SAFETY PRECAUTIONS

SAFETY PRECAUTIONS

Installation Environment

Safety considerations usually are directed toward machine design and the possibility of human error. In addition, the environment in which a machine is operated must not be overlooked as a potential safety hazard.

Most electrical equipment is safe when installed in a normal environment. However, if the environment is different from what most people consider to be normal, it is conceivable that the combination of the machine and the room air could present a hazardous combination. This is because heat (such as from fusing units) and electrical arcs (which can occur inside switches) have the ability to ignite flammable substances, including air.

When installing a machine, check to see if there is anything nearby which suggests that a potential hazard might exist. For example, a laboratory might use organic compounds which, when they evaporate, make the room air volatile. Potentially dangerous conditions might be seen or smelled. The presence of substances such as cleaners, paint thinners, gasoline, alcohol, solvents, explosives, or similar items should be cause for concern.

If conditions such as these exist, take appropriate action, such as one of the following suggestions.

∙Determine that the environment is controlled (such as through the use of an exhaust hood) so that an offending substance or its fumes cannot reach the machine.

∙Remove the offending substance.

∙Install the machine in a different location.

The specific remedy will vary from site to site, but the principles remain the same. To avoid the risk of injury or damage, be alert for changes in the environment when performing subsequent service on any machine, and take appropriate action.

Unauthorized Modifications

Konica copiers have gained a reputation for being reliable products. This has been attained by a combination of outstanding design and a knowledgeable service force.

The design of the copier is extremely important. It is the design process that determines tolerances and safety margins for mechanical, electrical, and electronic aspects. It is not reasonable to expect individuals not involved in product engineering to know what

effect may be caused by altering any aspect of the machine’s design. Such changes have the potential of degrading product performance and reducing safety margins.

For these reasons, installation of any modification not specifically authorized by Konica Business Machines U.S.A., Inc., is strictly prohibited.

The following list of prohibited actions is not all-inclu- sive, but demonstrates the intent of this policy.

∙Using an extension cord or any unauthorized power cord adapter.

∙Installing any fuse whose rating and physical size differs from that originally installed.

∙Using wire, paper clips, solder, etc., to replace or eliminate any fuse (including temperature fuses).

∙Removing (except for replacement) any air filter.

∙Defeating the operation of relays by any means (such as wedging paper between contacts).

∙Causing the machine to operate in a fashion other than as it was designed.

∙Making any change which might have a chance of defeating built-in safety features.

∙Using any unspecified replacement parts.

General Safety Guidelines

This copier has been examined in accordance with the laws pertaining to various product safety regulations prior to leaving the manufacturing facility to protect the operators and service personnel from injury. However, as with any operating device, components will break down through the wear-and-tear of everyday use, as will additional safety discrepancies be discovered. For this reason, it is important that the technician periodically performs safety checks on the copier to maintain optimum reliability and safety.

The following checks, not all-inclusive, should be made during each service call:

CAUTION: Avoid injury. Ensure that the copier is disconnected from its power source before continuing.

∙Look for sharp edges, burrs, and damage on all external covers and copier frame.

∙Inspect all cover hinges for wear (loose or broken).

∙Inspect cables for wear, frays, or pinched areas.

v

SAFETY PRECAUTIONS

∙Ensure that the power cord insulation is not damaged (no exposed electrical conductors).

∙Ensure that the power cord is properly mounted to the frame by cord clamps.

∙Check the continuity from the round lug (GND) of the power cord to the frame of the copier -- ensure continuity. An improperly grounded machine can cause an electrically-charged machine frame.

Safeguards During Service Calls

Confirm that all screws, parts, and wiring which are removed during maintenance are installed in their original positions.

∙When disconnecting connectors, do not pull the wiring, particularly on AC line wiring and high voltage parts.

∙Do not route the power cord where it is likely to be stepped on or crushed.

∙Carefully remove all toner and dirt adhering to any electrical units or electrodes.

∙After part replacement or repair work, route the wiring in such a way that it does not contact any burrs or sharp edges.

∙Do not make any adjustments outside of the specified range.

Applying Isopropyl Alcohol

Care should be exercised when using isopropyl alcohol, due to its flammability. When using alcohol to clean parts, observe the following precautions:

∙Remove power from the equipment.

∙Use alcohol in small quantities to avoid spillage or puddling. Any spillage should be cleaned up with rags and disposed of properly.

∙Be sure that there is adequate ventilation.

∙Allow a surface which has been in contact with alcohol to dry for a few minutes to ensure that the alcohol has evaporated completely before applying power or installing covers.

Summary

It is the responsibility of every technician to use professional skills when servicing Konica products. There are no short cuts to high-quality service. Each copier must be thoroughly inspected with respect to safety considerations as part of every routine service call. The operability of the copier, and more importantly, the safety of those who operate or service the copier, are directly dependent upon the conscientious effort of each and every technician.

Remember...when performing service calls, use good judgement (have a watchful eye) to identify safety hazards or potential safety hazards that may be present, and correct these problem areas as they are identified -- the safety of those who operate the copier as well as those who service the copier depend on it!

vi

DF-312

PRODUCT SPECIFICATIONS

Type

Type:

Sheet-through type reversible DF

Functions

Originals size: 11x17, 8.4x14, 8.5x11R, 8.5x5.5, 8.5x5.5R, 8.5x11

·All sizes are detected automatically.

·Mixing of original sizes possible.

Kinds of originals

Ordinary paper: 14 - 36 lb. fine quality paper Special paper: Paper feed and conveyance abil-

ity may sometimes be inferior to those of 14 to 36 lb. fine quality paper.

The following kinds of paper cannot be used:

·OHP film

·Blueprint masters

·Label paper

·Offset masters

·Pasted originals

Original curling: Less than 10 mm maximum

Machine Data

Power source: 24 V DC / 5 V (supplied from the main body)

Max. power consumption:

Less than 120 VA Weight: Approximately 32 lb.

Machine dimensions :

Unit: mm

570

590

150

Original

Curling

Maximum number of stacked originals:

50 sheets maximum (22 lb.)

Original read speed (copies per minute)

	Mode	Original size	Feed speed
	Single-sided
	original to Single-	8.5x11	65
	sided copy
	Dual-sided original	8.5x11	38
	to duplex copy
Original feed layout:		Face-up setting, centered, U-turn
		feed/straight paper exit, reversal

section mounted at paper exit side.

Original image read position:

At the slit glass section

Maintenance

Maintenance: Same as the main body

Operating Environment

Temperature:	50°F ~ 91°F
Humidity:	10% to 80%RH

Note: The contents of this manual may be changed without prior notice.

1

DF-312

CENTER CROSS-SECTIONAL DRAWING

		Separation roller	Paper feed tray
			Paper feed roller
Registration roller
Conveyance roller
Original		Pressure pulley
image read		Reversal roller
position
	Paper exit roller
Slit glass

DRIVE SYSTEM DRAWING

Original feed motor (M302)

Original feed CL	Separation roller
(CL302)	Paper feed roller

Original conveyance motor (M301)

Original pick-up CL (CL301)

Registration roller

Pressure pin

Paper exit roller

Conveyance roller

2

DF-312

ORIGINAL CONVEYANCE PROCESS

As the figure below shows, the DF-312 is composed of the paper feed section, conveyance section, reversal section and paper exit section.

	Conveyance	Paper feed section
	section
		Paper exit section
		Reversal section
	Slit glass
	(Read section)

The originals, which have been placed in the paper feed tray with the front side facing up, are fed starting with the topmost original. Originals that are fed are not conveyed to the original glass. Reading is carried out as the original passes by the slit glass section set midway through the conveyance path.

The operational modes of the DF-312 include three modes: (a) single side original copy mode, (b) double side original copy mode, (c) mixed original copy mode. The conveyance path is different for each mode.

Single side original copy mode (single side to single side copy, single side to double side copy)

The originals set in the paper feed tray are fed by means of the paper feed roller and separation roller to the position where PS306 (original registration) goes on.

	Separation roller
Registration roller	Paper feed roller
PS306 (Original registration)

When PS306 goes on, pre-feed is carried out by the registration roller and the original is conveyed to the conveyance roller at high speed. When PS308 (original conveyance) detects the leading edge of the original, the conveyance roller switches to scanning speed and conveys the original to the slit glass.

If there is next original at this time, pre-feed is carried out.

	Registration roller
	Conveyance roller
	PS308	PS306
	(Original conveyance)
		(Original registration)

Reading of the original is carried out when the original passes over the slit glass. Originals which have been read are conveyed around the circumference of the conveyance roller by closing of the flapper and are ejected to the paper exit section via the paper exit roller.

Next original
	Paper exit roller
Slit glass	Flapper

3

DF-312

Double side original copy mode

(double side to single side copy, double side to double side copy)

The original conveyance operation until the start of scanning for the front side of the 1st double side original is the same as that of the single side original copy mode.

When scanning starts and reading of the front side is completed, the original is conveyed to the reversal section when the flapper opens and the paper exit path is blocked.

When PS309 (original reversal) detects the leading edge of the original that has been conveyed to the reversal section and goes ON, pressure is applied to the pressure pulley. As a result, the reversal roller and pressure pulley clasp the original on both sides and convey it to the inside of the reversal section.

Flapper	Pressure pulley
Slit glass	Reversal roller
	PS309 (Original reversal)

When PS309 detects the trailing edge of the original and goes OFF, the reversal roller rotates in the reverse direction to feed the original from the reversal section to the conveyance roller. Since the original passes over the top of the flapper at this time, the front and back sides are reversed and the original is sent to the conveyance roller.

The conveyance roller conveys the original to PS308 (original conveyance) at high speed.

When PS308 detects the leading edge of the original, the conveyance roller switches back to scanning speed and conveys the original to the slit glass for the original to be scanned.

	Flapper	Pressure pulley
	PS308 (Original	Reversal roller
	conveyance
	PS309 (Original reversal)

When scanning of the back side starts, the flapper is opened. As a result, the original which has been read is conveyed to the inside of the reversal section again.

Flapper

When PS309 detects the trailing edge of the original and goes OFF, the reversal roller rotates in the reverse direction to feed the original from the reversal section to the conveyance roller. Since the flapper is closed at this time, the original is conveyed along the flapper and is ejected to the paper exit section via the paper exit roller.

	Next original		Paper exit roller
	Flapper		Reversal roller
		PS309 (Original reversal)

Mixed original copy mode

The mixed original copy mode can handle both the same series and different series of originals.

The size of the original in the conveyance direction is determined by the ON time of PS306, size detection operation take place prior to the scanning operation.

The original then stops at the scanning standby position. The subsequent operations are the same for all copy modes. For details on the size detection operation, refer to Paper Feed/Paper Eject section “Original Size Detection Control”.

4

DF-312

EXTERNAL SECTION

Composition

Open/close cover

Paper feed tray

Paper exit section

	Mechanism		If the jammed original is hard to remove, operate the pressure
			release lever to remove the pressure of the separation roller,
	Mechanisms	Methods
			and then remove the original.

1	Jam clearance	Open/close cover
		Release knob
		Conveyance guide open/close lever	Separation roller	Pressure release lever
		Pressure release lever
		Platen guide
	1: Jam clearance
	If a paper jam occurs during the feed process, open the open/
	close cover, raise the conveyance guide open/close lever, and
	rotate the release knob to remove the jammed original.
		Open/close cover
		Release knob
		Conveyance
		guide open/close
		lever
	Conveyance guide

5

DF-312

If a paper jam occurs during the reversal process, the jammed original can be removed by opening the platen guide.

Lock

Platen

guide

Disassembly and Reassembly

1.Removing and Reinstalling the Paper Dust Removing Pad

Caution: Be sure that the power cord has been unplugged from the power outlet.

a. Procedure

(1)Open the open/close cover.

(2)Remove the set screw, then remove the paper dust removing pad.

Paper dust removing pad

Set screw

(3)Reinstall the paper dust removing pad in the opposite sequence to removal.

2. Removing the RADF

Caution: Be sure that the power cord has been unplugged from the power outlet.

a. Procedure

(1)Remove the rear cover.

(2)Remove the set screw, then remove the connector cover.

(3)Remove the two connectors (CN100, CN102).

(4)Remove the two set screws, then withdraw the cable from the main body.

Cable

Set screws

Connector

cover

Connector

(CN102)

Connector

(CN100)

Set screw

(5)Remove the set screw from each, then remove the two stoppers.

(6)Remove the two set screws from each, then remove the two securing plates.

Set screw

Stopper

Securing

plate

Set

screws

6

DF-312

(7)Open the RADF.

(8)Remove the set screw from each while supporting the RADF, then remove the two securing plates.

(9)Remove the RADF from the main body.

2. Reinstalling the RADF

Caution: Be sure that the power cord has been unplugged from the power outlet.

a. Procedure

Securing plate/F

Set

screw

RADF

Caution: Be sure to support the RADF during this process as it may fall to the rear side when the securing plate/ F has been removed.

(1)Remove the two set screws, then remove the original stopper plate of the main body.

Set screw

Original stopper plate

Set screw

(2)Install the two RADF positioning jigs in the hole of the original stopper plate.

(3)After reinstalling the RADF, secure the two securing metal plates temporarily with the set screws each.

Caution: The double loop hole section of securing metal plate must be set in the guide screw.

Guide screw

Securing metal

plate

Set screw

Reference

hole

(round hole)

Reference

hole

(long hole)

RADF

positioning jigs

7

DF-312

(4)Close the RADF, and match the reference hole with the RADF positioning jig.

(5)When the two positions are matched, secure each of the two set screws of the securing metal plate.

Set screws

Securingmetal

plate

(6)Open the RADF and secure each of the set screw of the securing metal plate.

(7)Remove the two RADF positioning jigs, then install the original stopper plate.

(8)Close the RADF, and check whether or not the stoppers of the read section at the 2 locations contact with the slit glass.

		Stopper
		Projection
Slit glass	Stopper	Projection

(9)Adjust the adjustment screws A and B alternately so that both stoppers contact with the slit glass.

Caution: Repeat Step (8) to (9) until both stoppers make contact with the slit glass simultaneously.

(10)Reinstalling hereafter is performed in the opposite sequence to removal.

Adjustment
screw B	Adjustment
	screw A

8

						DF-312
PAPER FEED/PAPER EXIT SECTION
Composition
	Open/close cover					Registration
			Paper feed tray			roller
				Paper feed roller	Separation roller
			Paper exit tray
						Conveyance
						roller
			Original pressure			ADF fan
	Flapper solenoid			Original feed motor		(FM301)
			solenoid (SD302)
				(M302)	Original	Original
	(SD301)
					pick-up CL	conveyance motor
				Original feed CL
					(CL301)	(M301)
				(CL302)
	Mechanism
	Mechanisms		Methods
	Paper feed	Paper feed roller
	Double feed prevention	Double feed prevention pad
		Separation roller
	Conveyance	Conveyance roller
1	Conveyance path switching	Flapper
2	Reversal paper feed	Reversal roller pressure
		Reversal roller turn-back
	1: Conveyance path switching			Conveyance roller
	In the double side original copying, the conveyance path after
	the end of reading operations differs for front side copies and			Flapper
	back side copies. Change of the conveyance path is carried
	out by the flapper. Turning the flapper solenoid (SD301) ON				Flapper solenoid
	and OFF switches between the reversal section and the paper				(SD301)
	exit section.
				Flapper

9

DF-312

2: Reversal paper feed

During double side original copy operation, conveyance and reversal paper feed are activated by bringing the pressure pulleys into contact with the reversal roller. Pressure of the pressure pulleys is driven by the original pressure solenoid (SD302).

Pressure pulley

Reversal roller

Pressure pulleys

Original pressure

solenoid (SD302)

Disassembly and Reassembly

1.Removing and Reinstalling the paper feed roller/separation roller

Caution: Be sure that the power cord has been unplugged from the power outlet.

a. Procedure

(1)Remove the five set screws, and then remove the rear cover.

Set screws

Set screws

Rear cover

(2)Open the open/close cover.

(3)Rotate the gear until the two pressure pins on the pickup shaft point up.

Gear

Pressure

pins

Pickup shaft

Caution: The pickup shaft cannot be turned directly. Be sure to rotate it via the gear.

10

DF-312

(4)Remove the two springs.

(5)Remove the stop ring and slide the bearing to the side.

(6)Slide the paper feed roller assembly towards the front side, then remove it.

Bearing	Stop ring
Front
	Springs
	Paper feed
	roller assembly

(7)Remove the bearing.

(8)Remove the two stop rings, then remove the guide lever.

(9)Remove the separation roller and paper feed roller. Caution: When reinstalling each roller, pay attention to

correct roller orientation. (The correct orientation can be determined by looking at the side shape of the roller.)

Do not lose the spring of the paper feed roller.

Torque limitter

Separation roller

Stop rings

Bearing

Guide lever

Paper feed drive belt

Side shape of roller

Paper feed roller Springs

(10)Reinstall the paper feed roller and separation roller in the opposite sequence to removal.

2.Removing and Re-installing the double feed prevention pad

Caution: Be sure that the power cord has been unplugged from the power outlet.

a. Procedure

(1)Remove the paper feed roller assembly.

(2)Push the pressure release lever so that pressure on the double feed prevention pad is released.

Double feed

prevention pad

Pressure

release lever

(3)Push the double feed prevention pad down, slide it towards the paper feed tray, and then remove it.

Double feed prevention pad

Paper feed tray

(4)Reinstall the double feed prevention pad in the opposite sequence to removal.

11