dynamics gearbox practical

1. Aim
The aim of this experiment is to examine the automatic gearbox and determine the gear ratios for each gear (1st, 2nd, 3rd, 4th and reverse)

2. Apparatus

The gearbox in the laboratory

3. Method
i. Disassemble the gearbox ii. Count the number of gear teeth on every component iii. Develop a schematic for the gearbox iv. Record all the data
v. Assemble the gearbox vi. Calculate the transmission ratio for each gear

4. Results
Table 1: Gears teeth numbers

Number of teeth gears

Reverse
1st gear
2nd gear
3rd gear
Sun
26
20
20
17
Annulus
70
70
70
61
Planet
22
25
25
22

Figure 1: Schematic representation of the gearbox

5. Calculations

1st GEAR

Figure 2: 1st Gear sketch

Sun(s1)
Input
Arm(C1)
Output
Planet(P1)
Annulus(A1)
No. of teeth
20

25
70
Motion relative to frame x x x x
Motion relative to arm

0

-x
Total

x

0

=

=
=4.5
2nd Gear

Figure 3: 2nd gear sketch

Table 3: 2nd gear sketch

Sun(S2)
INPUT
Arm(C2)
Planet(P2)
Annulus(A2)
No. of teeth
20

25
70
Motion relative to frame x x x x
Motion relative to arm

0

-x
Total

x

0

Sun(s1)

Arm(C1)
Output
Planet(P1)
Annulus(A1)
No. of teeth
20

25
70
Motion relative to frame y y y y
Motion relative to arm

0

x-y
Total

y

x

The speed of S2 is equal to the speed of S3

=

=

=

= 2.531

3rd GEAR

Figure 4: 3rd gear sketch

Table 4: 3rd gear sketch

Sun(S3)
Input
Arm(C3)

Planet(P3)
Annulus(A3)
No. of teeth
17

22
61
Motion relative to frame x x x x
Motion relative to arm
-x
0

Total
0
x

Sun(S2)

Arm(C2)
Planet(P2)
Annulus(A2)
No. of teeth
20

25
70
Motion relative to frame y y y y
Motion relative to arm
-(
0

x-y