IBM Selectric - Page 51

4.
5.
Ti It Ring Homing - With a zero-ti It character hal f-cycled
and the tilt ring play removed in the negative direction
(Fig. 112a) (restoring direction), adjust the right hand
tilt pulley so that the rear of the tilt ring will rise about
.005" when the detent is manually allowed to seat inthe
detent notch (Fig. 112b).
FIGURE 112a. Tilt Detent Entry
Check the otherti It positions and then refine the homing
adjustment on the tilt selecti.on that provides the least
amount of rise to the rear of the tilt ring.
As a further check, remove the tilt ring play in the po-
sitive direction and observe the detent entry on the for-
ward side of the detent notch (Fig •. 112c). The detent
should enter far down the forward slope of the detent
notch but not so far that it contacts the tip of the tooth.
By homing the ti It ring off center, fovoring the positive
side of the detent notch, a maximum amount of wear
potentiai is achieved.
112 b.
Play Removed In
The Negative Direction
..........
"-
/
112 c.
\
I
/
Play Removed In
The Positive Direction
FIGURES 112b. and 112c. Tilt Detent Entry
Rotate Spring Tension - Adjust
the rotate spring in the
rocker so that it wi II have 1-7/8 to 2 pounds tension
when the machine is half-cycled using a lower case neg-
ative 5 character. The least amount of tension is pres-
ent in the spring when it is in this position. The type
head must be removed when making f'his adjustment.
2-33
The rotate spring tension is adiusted by turning the spi"ing
cage 'from the front (Fig. 113a). The cage can be tumed
clockwise to increase the tension by pull ing the c.
toward the left with a spring hook. The spring ctn.
retainer automatically snaps into position to retain the
adjustment. If tension is to be decreased, the retainer
must be pu II ed forward to a II ow the cage to rotate counter-
clockwise. Care must be taken to decrease the te'l1sion
slowly so that the cage does not spin freely. Spring
damage could otherwise result.
Retainer CI ip
FIGURE
113a. Rocker Assembly
Tensiol1 of the spring is critical in that it must. be ,....,.-
erly balanced with the springs of the wear compensator.
Excessive tension wi II overload the levers system and
increase weay' Insufficient tension will not providlt tl-.
torque necessary for rapid lower case negative roNte
operations. It will also affect the wear com~ ..
operation if the tension is not sufficient to overcome "-
compensator damper spring in the negative-5 !K>Siti.,..
The rotate spring tension should be measured with a ..-ifll!
scaleasindicatedbyFig. 113b. Using a 10"Mtr c~ -5
character, read the spring scale while slowly allowi,.
the sh i ft arm to move in towards its stop screw. T)e
spring scale should read 1-7/8 to 2 pounds just as the
Scale Should Be Read Just As
Shift Arm Reaches Rest Position
Shift Arm Moves
Toward Left
FIGURE 113b. Spring Scale Measurement For
Rotate Spring
Ad justment