PRINTED CIRCUIT BOARDS
ROUTINE MAINTENANCE
in-spection, cleaning, and lubrication. If a problem is discovered and the cause is not obvious, refer to the Troubleshooting chapter. If the cause of the problem has been determined, refer to Parts Removal and Adjustment section of this chapter to install a new component or to make an adjustment.
Preventative maintenance should be performed every six months or 1000 hours of motor on time whichever occurs first. Preventive maintenance procedures should include cleaning, adjustment, lubrication, and replacement of excessively worn parts or assemblies.
The repair philosophy for the TermiNet Printer gen-erally does not include the field repair of mechanical parts and assemblies but rather promotes the discard and replacement of such pieces. This would apply to all such items as clutches, drive motor, ribbon re-versing assemblies, etc. Printed circuit boards are factory repairable and can be returned for repair at the option of the user either in or out of warranty.
Certain printed circuit boards are considered field repairable by the General Electric Company, and are covered by separate field instructions. PCB field repairs are recommended only when the repair tech-nician is qualified and has the required tools, test equipment and parts as outlined in the "Shop Technical Instructions".
Normal use of the TermiNet Printer does not require readjustments at maintenance time due to wear in me-chanical parts. However, if adjustments are required see the Adjustment Procedures.
When used in a clean environment it is advisable to leave the Printer energized in "Standby" while not in actual use -- especially in a humid climate. If the environment is dirty or dusty the dust cover should be kept on the Printer with the Printer de-energized when not in use.
Never keep the dust cover on the Printer while it is energized.
VISUAL INSPECTION
Raise the cover and check the Printer as follows:
1. Check for accumulation of dust, dirt, or other foreign matter. If an accumulation of dust is under
the pulleys or line feed clutch, this is an indication of excessive wear of a pulley, clutch, or a drive belt.
2. Check for loose or missing parts.
3. Check for bent or broken print fingers.
4. Check for frayed or folded ribbon.
5. Check operation of the paper tensioner to see that it moves freely.
6. While holding the fan blade stationary, move the print belt back and forth and check for excessive play in the system. Too much play (movement greater than one finger width) indicates a loose pulley or drive belt.
Excessively tight belts will damage bearings and cause unnecessary loading. See adjust-ment tables for correct tension.
OPERATION CHECKS
Perform the checkout procedure in Chapter 2.
CLEANING AND LUBRICATION CLEANING
The platen, pressure rollers (under paper pan), and ribbon guide arms should be cleaned with alcohol to remove ink accumulations.
Do not apply alcohol or any other cleaning agent to an OILITE* bearing.
Accumulations of dirt inside the Printer can be removed with a cloth dampened in alcohol or blown out with dry compressed air (if available).
Type fingers can be cleaned by using a type cleaning brush backed by a sponge or soft cloth (see Figure
5-1).
Print belts should be removed, cleaned, adjusted, and re lubed during maintenance checks. Use a dry cloth to clean. Do not use water or chemicals. After clean-ing re-graphite the surface to eliminate static build up and spray with lubricant. Recheck guides and pulleys for correct adjustment if binding is present.
Print belts should move freely when pulleys are turned by hand.
Maintenance, Routine Maintenance
LUBRICATION
1. When cleaning parts, do not use alcohol or any other cleaning agent on OILITE bearings.
2. Use a good grade of non-detergent, inhibited, number 10 SAE oil. Do not use household variety, sewing machine, or general purpose oils unless it is certain that the specifications of the recommended oil are met.
3. After lubrication of a given area, work oil into friction points as well as possible, and thoroughly wipe away all excess oil.
LUBRICATION TABLE
The following table points out the parts to lubricate and the methods in which the parts are to be lubri-cated. Read table thoroughly before starting.
GEH-2185
PTM-30!1
Figure 5-1. Cleaning Type Fingers.
LUBRICATION POINT
I
Rear Idler PulleyI
Left J ackshaft Bearing Right Jackshaft Bearing Line Feed Clutch Platen Drive Gears
Line Feed Idler Gear
I
Platen Drive Gear
Fractional Line Space Gear General
I
I
Platen BearingsI l
Table 5-1 Lubrication Points (Reference Figures 5-2 thru 5-5)
METHOD - Remove belt and pulley.
- Wipe bearing clean with clean cloth.
- Wipe bearing shaft clean and apply two drops of oil.
- Reinstall pulley.
- Apply two irops between pulley and side frame.
- Apply two drops of oil on shaft adjacent to end of bearing on inside of the side frame.
- Apply two drops between the "E" ring and clutch housing.
- Remove any dried grease and dirt from gears and oil holes.
- Apply two drops of oil in oil hole.
- Apply one drop of oil on shaft at each end of gear.
- Press platen knob in and apply two drops of oil to shaft in fractional line space gear.
- Apply thin film of oil to teeth of each gear (pipe cleaner or small brush can be used). Start Printer and make consecutive line feeds to work in oil.
- Remove platen. (Refer to Section 2. )
- Remove "C" ring and bearing from one end of platen.
- Wipe platen shaft and bearing clean.
- Apply two drops of oil to shaft and reinstall bearing and "C"
ring on shaft.
- Repeat process for other end of platen and reinstall platen.
(contmued)
GEH-2185 Maintenance, Routine Maintenance Table 5-1. Lubrication Points l_continuedl
LUBRICATION POINT METHOD
Platen Knob Shaft Bearing - Remove dried grease and dirt from oil hole and apply one drop of oil in hole.
- Push in platen knob and rotate several times to work in oil. Repeat process with another drop of oil.
*Forms Tractor - Apply one drop on idler gear bearing under left cover. DO NOT OIL ANY OTHER PARTS ON THE FORMS TRACTOR.
Ribbon Reversing Mechanisms - Remove ribbon reversing mechanisms. (Refer to Section 2. ) - Wipe entire mechanism clean.
- Apply one drop of oil to each shaft of the 3 drive gears.
- Manually rotate gears to work in oil.
- Thoroughly wipe off all excess oil.
Ribbon Lift Arm Shaft Bearing - Apply one drop of oil at each bearing.
Print·Belt - Remove and clean with a dry cloth or dry fiber brush. Use no chemicals. Coat surface with graphite (anti-static) solution GE 44A410695-G01 and spray with aerosol dry lubricant GE 44A417371. (If print belt seizes check alignment of guides and pulleys. )
*Special paper handling option
LEFT MECHANISM RIGHT MECHANISM PTM-'.3041
Figure 5-2. Lubrication Points - Ribbon Reversing Mechanisms.
Maintenance, Routine Maintenance
PLATEN KNOB SHAFT BEARING
Figure 5-3. Lubrication Points - Printer Left Side.