Unimog U500, Инструкция по монтажу

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Body and Implement Mounting Guidelines U500 North America Mechanical drive of implements
August 2005 Page 177 of
294
Power take-off shaft guards
Rotating shafts and other PTO – components, which could cause
accidents, must be equipped with protection devices. The guards
for rotating parts shall be provided by the implement manufacturer.
The power take-off shaft drive must never be operated without
shaft guards. The standard / original power take-off shaft guard
must not be removed. Following the removal of the drive shaft from
the PTO-drive, the protective cap must be placed on the stub end
of the PTO output shaft at the vehicle.
5.9.2 Usable power output of the power take-off shaft
The permissible power output at the PTO shaft depends on appli-
cation conditions, e.g. operating duration, temperatures and kind of
application. The usable power output at the power take-off shaft
further depends on the engine speed, engine power output etc.
(see Section 5.6 Maximum available power output of the PTO’s,
page 171) and also on the angle
β
of the drive shaft from the PTO
to the implement (see Figure 5.8 and Table 5.5). The maximum
continuous PTO shaft power output is 201 hp / 150 kW. This is lim-
ited realized with the electronic engine control and cannot be
changed. The limitation of the engine torque output (not PTO shaft
torque!) with engaged PTO shaft is 590 lb
⋅
ft / 800 Nm.
Calculation of the usable PTO shaft power output:
PTO shaft power output:
PTOshaft
PTOshaft
PTOshaft
M
n
P *
60
* * 2
π
=
PTO shaft torque output:
( )
s auxiliarie engine PTOshaft
M M i M
− =
* *
η
Torque of auxiliaries:
ive tractiondr or ACcompress alternator hydraulic fan s auxiliarie
M M M M M M
+ + + + =
Min. torque of auxiliaries:
M
auxiliaries
= 112 Nm / 82.6
lb
⋅
ft
Efficiency factor of the PTO transm.:
η
= 0.97
PTO shaft speed: n
PTOshaft
= 1,000 rpm
Ratio of the PTO transmission: i = 2.139
Example:
( )
( )
ft lb M
ft lb M M i M
PTOshaft
s auxiliarie engine PTOshaft
⋅ =
⋅ − = − =
053 , 1
6 . 82 590 * 97 . 0 * 139 . 2 * *
η
hp
s
ft lb
P
ft lb
s
M
n
P
PTOshaft
PTOshaft
PTOshaft
PTOshaft
5 . 200 270 , 110
053 , 1 *
60
000 , 1
* * 2 *
60
* * 2
=
⋅
=
⋅ = =
π π
Maximal permissible
engine torque
Maximal power output at
the PTO shaft at 1,000 rpm
Drive shaft
angle
β
[lb
⋅
ft]
[Nm] [hp] [kW]
β ≤
15
°
590 800* 201 150
15
° ≤ β ≤
20
°
502 680 166 124
20
° ≤ β ≤
25
°
428 580 137 102
25
° ≤ β ≤
30
°
369 500 113 84
Table 5.5: PTO shaft power output
*Note: Ex factory adjusted engine torque with PTO shaft engaged.
β
β
Figure 5.8: Drive shaft angle
β
Further conditions:
•
Drive shaft in W or Z arrangement (see page 190 and the fol-
lowing)
•
Drive shaft angles larger than 30
°
are not permitted