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Full text of "Monroe MSB257: Carriage shift of LA-5 and LA-6 machines"

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MACHINE SERVICE BULLETIN NO. 257 

SUBJECT: Carriage Shift of LA-5 

and LA-6 Machines 

DATE: ' July 31, 1939 



TO ALL OFFICES: 

In order to obtain a satisfactory shift of the carriage on LA-5 and LA-6 model 
machines after all regular adjustments have been checked, servicemen have oc- 
casionally resorted to taking up on the clutch on the jack shaft until it failed 
to function as a slip clutch. To eliminate the need of such a practice, we sug- 
gest the removal of stock from the 4-0-731 coupling lever as illustrated on Plate 
2 of this bulletin and the readjusting of the double arm latch 4717 1/8. Here- 
tofore offset ( D I was adjusted to (C) so that when the division lever was moved 
into operating position, (D) would latch under the step of (C) with as little 
excess clearance as possible and in order to insure the latching of (D) the 
4717 I /8 was adjusted somewhat low. The natural result of this low adjustment 
was a loss of shift mechanism movement. 

To provide an upward adjustment of the 4717 1/8 by means of eccentric (G) with- 
out the possibility of it failing to latch under the step of (C) during the minus 
bumper stroke following an over-carry trip, stock could be removed from (A) as 
shown in the insets on Plate 2. The absence of this stock permits (Cl to pivot 
rearward slightly more during the minus bumper stroke, thereby, allowing offset 
(D) to latch with (Cl although the 4717 1/8 was adjusted higher than previous- 
ly. Also, it is no longer necessary for (Dl to latch under the step of (Cl when 
the division lever is moved toward the carriage. 

It will be interesting to note that after making this adjustment, (HI will be 
moved downward its entire distance before (A) starts to move under roller. (6), 
thus proving that the grinding out of stock does not cause any loss of shift 

power. 

After doing this it will be found that the slip clutch can be let out (friction 
reduced I considerably without retarding the carriage shift. 

Roller (01 can be adjusted lower by loosening nut (F). However, its downward 
adjustment is limited due to interference with a stud on the machine stopping 
lever. 

The journey of the cycle stop arm (E) to the bumper pad following an overcarry 
trip in minus, causes an idle movement of (A) in relation to (8), but following 
an over-carry trip in plus, (A) contacts and pushes (Bl forward, causing a 
carriage shift. 



F. M. Smith 



General Service Manager 



MACHINE SERVICE BULLETIN NO* 257 



Plate 2 




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a. 

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x 

CO 



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<5 

cn 

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