Komatsu 75001, Shop Manual

Page: 278 / 1293

SEN03831-00
WA250, 250PZ-6 10-700
17
700 Work equipment
Bucket positioner and boom kick-out
Outline
Bucket positioner or fork positioner
q
The bucket positioner is driven electrically.
When the bucket or fork is returned to an angle
from the dump position to the tilt position, the
bucket positioner returns the work equipment
(bucket or fork) control lever from the "tilt" posi-
tion to the "hold" position to automatically stop
the bucket or fork at a proper digging angle or
lift angle.
q
Bar (4) is fixed to the rod side of bucket cylin-
der (5). And proximity switches (1) and (2) are
fixed to the cylinder side.
q
Moving the work equipment (bucket or fork)
control lever from "dump" position to "tilt" posi-
tion moves the rod of bucket cylinder (5)
toward the machine front side.
As bar (4) moves a specific distance, proximity
switches (1) and (2) detect that it is away from
the sensing face, and return the work equip-
ment (bucket or fork) control lever to "hold"
position.
q
While the attachment selector switch of the
right-hand console is in the "BUCKET" posi-
tion, proximity switch (2) operates. While the
former is in the "FORK" position, proximity
switch (1) operates.
Boom kick-out
q
The boom kick-out is driven electrically. As the
lift arm is raised to an angle before reaching
the maximum height, the boom kick-out returns
the work equipment (lift arm) control lever from
the "raise" position to the "hold" position to
stop the lift arm automatically at a desired
height.
q
Plate (7) is fixed to lift arm (6). And proximity
switch (3) is fixed to the front frame.
q
Moving the work equipment (lift arm) control
lever from "lower" position to "raise" position
moves lift arm (6) upward.
As plate (7) moves a specific distance, proxim-
ity switch (3) detects that it is away form the
sensing face, and returns the work equipment
(lift arm) control lever to "hold" position.