附录 A
英文资料
Research on Design of Planetary Gearbox
Nanjing Artillery College RaoZhenggang
［Abstract］The design and calculations of planetary gearbox are detailedly discussed in this thesis.The calculations of structure
parameters,transmissionratio,torque of each shaft,braketorque,lockingmoment,and transmission power are explained here.Hence,this paper is of much importance to the design of planetary gearbox of caterpillar vehicle,tank,artillery and engineering mechanics.
Key words: Planetary gearbox Structure parameter Torque Power
c)Clutch L locks internal gear rign b and swiveling jib H(see figure 3,c)
When clutch L combines gear ring b and swiveling jib H into one
whole,n b=n H.Then torque T A of input shaft A can transmit through two ways:one is to transmit to output shaft B through central gear a,planet gear g and swiveling jib H;the other is to B by central gear a,planet gear g,internal gear ring b and clutch L.At this moment,T A=T a,T B=-T A and locking moment T L is equal to the torque of internal gear ring T b,T L=T b.According to formula (4-3),the locking moment T L is
T L=T b=pT a(4-11)
From the formula above,when central gear a inputs and swiveling jib H outputs,the locking moment T L of the first scheme is the lowest and the size is smaller.So as to 2K-H(A) planetary gearbox,the first scheme is more reasonable.
(1)Suppose internal gear ring b inputs,swiveling jib H outputs(see figure
4),T A=T b,T B=T H;Let us discuss the locking moment T1 of friction clutch of three different locking pattern.
a)Clutch L locks intermal gear ring b and centra gear a(see figure 4,a),that is
n a=n b=n H;then the planet bar becomes a whole and rotates.So
T B=-T A,T1=T a.According to formula (4-2),T L is:
(4-12)
So,
b)Clutch L locks central gear a and swiveling jib H(see figure 4,b),that is n H=n a and T L=T a.So T L is
So,
(4-13)
c)Clutch L locks internal gear ring b and swiveling jib H(see figure 4,c),that is n H=n b and T L=T b.Since the clutch L links input shaft A and output shaft B,locking moment T L is equal to the torque transmitted by shaft A,namely T L=T b=T A.So the locking moment T L is
T L=T A
From the formula above,when internal gear ring inputs and swiveling jib outputs,locking moment T L of the first scheme is the lowest.So it is the best to adopt the first locking scheme.
After T L is calculated,the necessary control units can be adopted to obtain the friction clutch with smaller size.But,infact,the best locking scheme can't be always realized due to difficulty instructrualdistribution.Under this situation,the locking scheme should be adopted to get more compact structure of clutch and smaller size of the gearbox.
5Calculation of efficiency of planetary gearbox
As to multi-degree planetary geabox,the ratio of output power P B and input power P A is called the transmission efficiency of planetary ly,
(5-1)
Where,T A、n A—torque and rotational speed of input shaft A；
T B、n B—torque and rotational speed of output shaft B.
Ratio n A/n B=i p is kinematics transmission ratio;ratio-T B/T A=i p～is dynamics
