Lower Thread Trimmer Mechanism - Brother LH4-B800E Service Manual

3. ASSEMBLY

3-2. Lower thread trimmer mechanism

t r
q
e
i
u
o
!0
!3
Insert the roller shaft q into the lower thread trimmer cam lever w, and secure it by tightening the nut e. Place the roller r onto
the roller shaft q, and then install the retaining ring t.
Install the lower thread trimmer cam connecting rod y to the lower thread trimmer cam o with the driving lever roller u and the
shoulder screw i. (Lower thread trimmer cam assembly !1 )
Install the cover ! 0 to the bed.
Pass the lower thread trimmer cam assembly !1 through the cover !0 and install it to the bed with the two lever shafts !2 . Tighten
the two set screws !3 so that the lower thread trimmer cam assembly !1 moves smoothly without any play.
Insert the roller r into the lower thread trimmer cam o, and then install it to the bed with the lower thread trimming cam shaft !4 ,
washer !5 and retaining ring !6 . Secure by tightening the set screw !7 .
Connect the presser lifter connecting rod set !8 and the lower thread trimmer cam lever w using plain washer D @0 , and the bolt
@1 .
Install the lower thread trimmer link assembly @2 with the shoulder screw @3 .
Connect the lower thread trimmer link assembly @ 2 and the lower thread trimmer cam connecting rod y with the shoulder screw
@4 .
Install the opening plate assembly @5 with the shoulder screw @6 . Install the plate spring @7 as shown in the illustration.
3 - 2
w
!1
y
!1
!2
Apply grease to !2
LH4-B800E
Apply grease to cam groove
o and to !4
o
!4
!7
!5
r
!6
!8
w
@2
@3
@2 @4
@6
@5
@7
!4
!5
!6
!7
@1
Apply grease to !9
@0
!9
Apply grease to @3
y