Kubota B1830, Workshop Manual

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TRANSMISSION B1830,B2230,B2530,B3030, WSM
3-M35
[5] ONE-WAY CLUTCH SYSTEM
In manual transmission models, a mechanical PTO
is adopted.
The one-way PTO clutch is located between the first
shift shaft (1) and the PTO clutch shaft (18).
The one-way clutch is composed of the first shift
shaft (1), the one-way clutch spring (4), the one-way
clutch cam (5), the one-way clutch spline boss (9) and
the one-way clutch shaft (18).
The one-way clutch cam (15) is splined to the first
shift shaft (1), and the one-way clutch spline boss (9) is
splined to the PTO clutch shaft (18).
Both the one-way clutch cam (5) and the one-way
clutch spline boss (9) are engaged with each other by the
force of the one-way clutch spring (4).
While the first shift shaft (1) is driving the PTO clutch
shaft (18), both the one-way clutch cam and the one-way
clutch spline boss (9) will remain engaged.
However, when the PTO shaft drives a rotary mower,
for example, and if the engine speed is lowered, the
one-way clutch spline boss (9) on the PTO clutch shaft
(18) will overrun.
This overrunning is caused by the inertia of the
mower's blades.
Then, engagement will not take place until the first
shift shaft (1) is running faster than the one-way clutch
PTO clutch shaft (18).
In this way, the one-way clutch protects the
transmission and the engine against damage, by
allowing the PTO shaft, the first shift shaft (1) and the
PTO clutch shaft (18) to overrun if the first shift shaft (1)
over speeds.
9Y1210003TRM0035US0
(1) First Shift Shaft
(2) Ball Bearing
(3) Collar (1.8)
(4) One-way Clutch Spring
(5) One-way Clutch Cam
(6) Bearing Holder
(7) Cir-clip
(8) Cir-clip
(9) One-way Clutch Spline Boss
(10) Shifter (PTO ON/OFF)
(11) Clutch Spring (12) PTO Brake Spline Boss
(13) Needle Bearing
(14) Thrust Ball Baring
(15) Cir-clip
(16) Thrust Collar
(17) Needle Bearing
(18) PTO Clutch Shaft
(19) PTO ON/OFF Shift Lever
(20) PTO Shift Lever
a: One-way Clutch Section
KiSC issued 05, 2012 A