(2)电动机所需功率 P
ip
(3)液压马达的输出转矩 T
M
(4)液压马达的输出功率 P
OM
(5)液压马达的输出转速 n
M
[题目 1]在图 4-1(a)所示的液压回路中，所采用的是限压式变量叶片泵。图(b)示出了该泵
调定的流压特性。调速阀调定的流量为 Q
2
=2.5L／min，液压缸两腔的有效作用面积
A
1
=50cm
2
、A2=25cm
2
。在不考虑任何损失时，试计算：(1)液压缸左腔的压力 p
l
；(2)当负载
F
L
=0 时的 p
2
；(3)当负载 F
L
=9000N 时的 p
2
。
图 4-1
kW
P
P
P
mp
Vp
P
p
p
iP
63
.
2
95
.
0
9
.
0
25
.
2
0
0
=
×
=
⋅
=
=
η
η
η
Nm
q
P
q
P
T
mM
M
p
mM
M
M
M
1
.
15
95
.
0
2
10
10
10
10
2
2
6
6
=
×
×
×
×
=
⋅
⋅
=
⋅
⋅
=
−
π
η
π
η
π
kW
P
P
P
mM
VM
p
M
iM
M
92
.
1
95
.
0
9
.
0
25
.
2
0
0
=
×
×
=
⋅
⋅
=
⋅
=
η
η
η
min
/
1215
10
9
.
0
9
.
0
1500
10
r
q
n
q
q
Q
q
Q
q
Q
q
Q
n
M
VM
Vp
P
P
M
VM
Vp
iP
M
VM
P
M
VM
M
M
iM
M
=
×
×
×
=
⋅
⋅
⋅
=
⋅
⋅
=
⋅
=
⋅
=
=
η
η
η
η
η
η