1从能量的观点来看,液压泵和液压马达有什么区别和联系?从结构上来看,液压泵和液压马达又有什么区别和联系?答:从能量的观点来看,液压泵是将驱动电机的机械能转换成液压系统中的油液压力能,是液压传动系统的动力元件;而液压马达是将输入的压力能转换为机械能,输出扭矩和转速,是液压传动系统的执行元件。它们都是能量转换装置。从结构上来看,它们基本相同,都是靠密封容积的变化来工作的。4.3在供油流量q不变的情况下,要使单杆活塞式液压缸的活塞杆伸出速度相等和回程速度相等,油路应该差动连接,而且活塞杆的直径d与活塞直径D的关系为:D=(根号2)乘以d.4.65.1 已知单杆液压缸缸筒直径 =100mm, 活塞杆直径 =50mm, 工作压力 _(1)=2-|||-MPa,流量为 =10L/min, 回油背压力为 _(2)=0.5MPa, 试求活塞往复运动时的推力和运-|||-动速度。-|||-解:(1)无杆腔进油时: _(1)=(P)_(1)(A)_(1)-(P)_(2)cdot (A)_(2)=dfrac (pi )(4)[ ((P)_(1)-(P)_(2))(D)^2+(P)_(2)(d)^2] -|||-_(1)=dfrac (pi )(4)times [ (2times (10)^6-0.5times (10)^6)times (0.1)^2+0.5times (10)^6times (0.05)^7] =1.08times (10)^4N-|||-_(1)=dfrac (q)({A)_(1)}=dfrac (10times {10)^-3}(dfrac {pi )(4)times (0.1)^2times 60}=0.021m/s-|||-(2)有杆腔进油时: _(2)=(P)_(1)(A)_(2)-(P)_(2)(A)_(1)=dfrac (pi )(4)[ ((P)_(1)-(P)_(2))(D)^2-(P)_(1)(d)^2] -|||-_(2)=dfrac (pi )(4)times [ (2times (10)^6-0.5times (10)^6)times (0.1)^2-2times (10)^6times (0.05)^2] =0.785times (10)^4N5.1 已知单杆液压缸缸筒直径 =100mm, 活塞杆直径 =50mm, 工作压力 _(1)=2-|||-MPa,流量为 =10L/min, 回油背压力为 _(2)=0.5MPa, 试求活塞往复运动时的推力和运-|||-动速度。-|||-解:(1)无杆腔进油时: _(1)=(P)_(1)(A)_(1)-(P)_(2)cdot (A)_(2)=dfrac (pi )(4)[ ((P)_(1)-(P)_(2))(D)^2+(P)_(2)(d)^2] -|||-_(1)=dfrac (pi )(4)times [ (2times (10)^6-0.5times (10)^6)times (0.1)^2+0.5times (10)^6times (0.05)^7] =1.08times (10)^4N-|||-_(1)=dfrac (q)({A)_(1)}=dfrac (10times {10)^-3}(dfrac {pi )(4)times (0.1)^2times 60}=0.021m/s-|||-(2)有杆腔进油时: _(2)=(P)_(1)(A)_(2)-(P)_(2)(A)_(1)=dfrac (pi )(4)[ ((P)_(1)-(P)_(2))(D)^2-(P)_(1)(d)^2] -|||-_(2)=dfrac (pi )(4)times [ (2times (10)^6-0.5times (10)^6)times (0.1)^2-2times (10)^6times (0.05)^2] =0.785times (10)^4N4.75.1 已知单杆液压缸缸筒直径 =100mm, 活塞杆直径 =50mm, 工作压力 _(1)=2-|||-MPa,流量为 =10L/min, 回油背压力为 _(2)=0.5MPa, 试求活塞往复运动时的推力和运-|||-动速度。-|||-解:(1)无杆腔进油时: _(1)=(P)_(1)(A)_(1)-(P)_(2)cdot (A)_(2)=dfrac (pi )(4)[ ((P)_(1)-(P)_(2))(D)^2+(P)_(2)(d)^2] -|||-_(1)=dfrac (pi )(4)times [ (2times (10)^6-0.5times (10)^6)times (0.1)^2+0.5times (10)^6times (0.05)^7] =1.08times (10)^4N-|||-_(1)=dfrac (q)({A)_(1)}=dfrac (10times {10)^-3}(dfrac {pi )(4)times (0.1)^2times 60}=0.021m/s-|||-(2)有杆腔进油时: _(2)=(P)_(1)(A)_(2)-(P)_(2)(A)_(1)=dfrac (pi )(4)[ ((P)_(1)-(P)_(2))(D)^2-(P)_(1)(d)^2] -|||-_(2)=dfrac (pi )(4)times [ (2times (10)^6-0.5times (10)^6)times (0.1)^2-2times (10)^6times (0.05)^2] =0.785times (10)^4N4.85.1 已知单杆液压缸缸筒直径 =100mm, 活塞杆直径 =50mm, 工作压力 _(1)=2-|||-MPa,流量为 =10L/min, 回油背压力为 _(2)=0.5MPa, 试求活塞往复运动时的推力和运-|||-动速度。-|||-解:(1)无杆腔进油时: _(1)=(P)_(1)(A)_(1)-(P)_(2)cdot (A)_(2)=dfrac (pi )(4)[ ((P)_(1)-(P)_(2))(D)^2+(P)_(2)(d)^2] -|||-_(1)=dfrac (pi )(4)times [ (2times (10)^6-0.5times (10)^6)times (0.1)^2+0.5times (10)^6times (0.05)^7] =1.08times (10)^4N-|||-_(1)=dfrac (q)({A)_(1)}=dfrac (10times {10)^-3}(dfrac {pi )(4)times (0.1)^2times 60}=0.021m/s-|||-(2)有杆腔进油时: _(2)=(P)_(1)(A)_(2)-(P)_(2)(A)_(1)=dfrac (pi )(4)[ ((P)_(1)-(P)_(2))(D)^2-(P)_(1)(d)^2] -|||-_(2)=dfrac (pi )(4)times [ (2times (10)^6-0.5times (10)^6)times (0.1)^2-2times (10)^6times (0.05)^2] =0.785times (10)^4N4.95.1 已知单杆液压缸缸筒直径 =100mm, 活塞杆直径 =50mm, 工作压力 _(1)=2-|||-MPa,流量为 =10L/min, 回油背压力为 _(2)=0.5MPa, 试求活塞往复运动时的推力和运-|||-动速度。-|||-解:(1)无杆腔进油时: _(1)=(P)_(1)(A)_(1)-(P)_(2)cdot (A)_(2)=dfrac (pi )(4)[ ((P)_(1)-(P)_(2))(D)^2+(P)_(2)(d)^2] -|||-_(1)=dfrac (pi )(4)times [ (2times (10)^6-0.5times (10)^6)times (0.1)^2+0.5times (10)^6times (0.05)^7] =1.08times (10)^4N-|||-_(1)=dfrac (q)({A)_(1)}=dfrac (10times {10)^-3}(dfrac {pi )(4)times (0.1)^2times 60}=0.021m/s-|||-(2)有杆腔进油时: _(2)=(P)_(1)(A)_(2)-(P)_(2)(A)_(1)=dfrac (pi )(4)[ ((P)_(1)-(P)_(2))(D)^2-(P)_(1)(d)^2] -|||-_(2)=dfrac (pi )(4)times [ (2times (10)^6-0.5times (10)^6)times (0.1)^2-2times (10)^6times (0.05)^2] =0.785times (10)^4N5.1 已知单杆液压缸缸筒直径 =100mm, 活塞杆直径 =50mm, 工作压力 _(1)=2-|||-MPa,流量为 =10L/min, 回油背压力为 _(2)=0.5MPa, 试求活塞往复运动时的推力和运-|||-动速度。-|||-解:(1)无杆腔进油时: _(1)=(P)_(1)(A)_(1)-(P)_(2)cdot (A)_(2)=dfrac (pi )(4)[ ((P)_(1)-(P)_(2))(D)^2+(P)_(2)(d)^2] -|||-_(1)=dfrac (pi )(4)times [ (2times (10)^6-0.5times (10)^6)times (0.1)^2+0.5times (10)^6times (0.05)^7] =1.08times (10)^4N-|||-_(1)=dfrac (q)({A)_(1)}=dfrac (10times {10)^-3}(dfrac {pi )(4)times (0.1)^2times 60}=0.021m/s-|||-(2)有杆腔进油时: _(2)=(P)_(1)(A)_(2)-(P)_(2)(A)_(1)=dfrac (pi )(4)[ ((P)_(1)-(P)_(2))(D)^2-(P)_(1)(d)^2] -|||-_(2)=dfrac (pi )(4)times [ (2times (10)^6-0.5times (10)^6)times (0.1)^2-2times (10)^6times (0.05)^2] =0.785times (10)^4N4.105.1 已知单杆液压缸缸筒直径 =100mm, 活塞杆直径 =50mm, 工作压力 _(1)=2-|||-MPa,流量为 =10L/min, 回油背压力为 _(2)=0.5MPa, 试求活塞往复运动时的推力和运-|||-动速度。-|||-解:(1)无杆腔进油时: _(1)=(P)_(1)(A)_(1)-(P)_(2)cdot (A)_(2)=dfrac (pi )(4)[ ((P)_(1)-(P)_(2))(D)^2+(P)_(2)(d)^2] -|||-_(1)=dfrac (pi )(4)times [ (2times (10)^6-0.5times (10)^6)times (0.1)^2+0.5times (10)^6times (0.05)^7] =1.08times (10)^4N-|||-_(1)=dfrac (q)({A)_(1)}=dfrac (10times {10)^-3}(dfrac {pi )(4)times (0.1)^2times 60}=0.021m/s-|||-(2)有杆腔进油时: _(2)=(P)_(1)(A)_(2)-(P)_(2)(A)_(1)=dfrac (pi )(4)[ ((P)_(1)-(P)_(2))(D)^2-(P)_(1)(d)^2] -|||-_(2)=dfrac (pi )(4)times [ (2times (10)^6-0.5times (10)^6)times (0.1)^2-2times (10)^6times (0.05)^2] =0.785times (10)^4N4.115.1 已知单杆液压缸缸筒直径 =100mm, 活塞杆直径 =50mm, 工作压力 _(1)=2-|||-MPa,流量为 =10L/min, 回油背压力为 _(2)=0.5MPa, 试求活塞往复运动时的推力和运-|||-动速度。-|||-解:(1)无杆腔进油时: _(1)=(P)_(1)(A)_(1)-(P)_(2)cdot (A)_(2)=dfrac (pi )(4)[ ((P)_(1)-(P)_(2))(D)^2+(P)_(2)(d)^2] -|||-_(1)=dfrac (pi )(4)times [ (2times (10)^6-0.5times (10)^6)times (0.1)^2+0.5times (10)^6times (0.05)^7] =1.08times (10)^4N-|||-_(1)=dfrac (q)({A)_(1)}=dfrac (10times {10)^-3}(dfrac {pi )(4)times (0.1)^2times 60}=0.021m/s-|||-(2)有杆腔进油时: _(2)=(P)_(1)(A)_(2)-(P)_(2)(A)_(1)=dfrac (pi )(4)[ ((P)_(1)-(P)_(2))(D)^2-(P)_(1)(d)^2] -|||-_(2)=dfrac (pi )(4)times [ (2times (10)^6-0.5times (10)^6)times (0.1)^2-2times (10)^6times (0.05)^2] =0.785times (10)^4N4.12 设计一单杆活塞液压缸,要求快进时为差动连接,快进和快退(有杆腔进油)时的速度均为6 m/min。工进时(无杆腔进油,非差动连接)可驱动的负载为F = 25 000N,回油背压力为0.25 MPa,采用额定压力为6.3 MPa、额定流量为25 L/min的液压泵,试确定:(1)缸筒内径和活塞杆直径各是多少?(2)缸筒壁厚(缸筒材料选用无缝钢管)是多少?