Type "Morris"type morris

Another "Meccano"-inspired design. Based on the "Lanchester" type. , the special feature is the attachment of the left roadwheel (5) to the differential's runner. This is achieved by holding the runner's horizontal shaft from its outer ends in bearings on spacers bolted to wheel 7. The adapted equations:
(a:) n4 * rot4 + n9 * rot9 - (n4 + n9) * rot7 = 0
(b:) n2 * rot2 - n3 * rot3 = 0
(c:) n6 * rot6 - n7 * rot7 = 0
(d:) n10 * rot10 + n11 * rot11 = 0
 The remaining constraints:
(e:) rot1 = rot2
(f:) rot3 = rot4
(g:) rot5 = rot6
(h:) rot9 = rot10
Composition (POV is from top respectively from far right):
(e=>) rot1 = rot2
(b=>)    = (n3 / n2) * rot3
(f=>)    = (n3 / n2) * rot4
(g=>) rot5 = rot6
(c=>)    = (n7 / n6) * rot7
(d=>) rot11 = (-1) * (n10 / n11) * rot10
(h=>)    = (-1) * (n10 / n11) * rot9
(a=>i:) n4 * (n2 / n3) * rot1 - n9 * (n11 / n10)* rot11 - (n4 + n9) * (n6 / n7) * rot5 = 0
To make it "south-pointing" requires, that if rot5 is held 0, rot11 has to be exactly one turn when wheel 1 of diameter d1 covered one full circle (centre at wheel 5's contact to the ground, radius equal to track width t):
(j:) d1 * rot1 * PI = 2 * t * PI
(k:) rot11 = 1
(l:) rot5 = 0
(i=>) n4 * (n2 / n3) * rot1 - n9 * (n11 / n10) * 1 - (n4 + n9) * (n6 / n7) * 0 = 0
rot1 = (n3 / n2) * (n9 / n4) * (n11 / n10)
(j=>) d1 = 2 * t / rot1
The same method can be applied to calculate the required size for wheel 5: If rot1 is held 0, rot11 has to be exactly one turn when wheel 5 of diameter d5 covered one full circle (this time centre at wheel 1's contact to the ground, radius equal to track width t):
(m:) d5 * rot5 * PI = 2 * t * PI
(n:) rot1 = 0
(i=>) n4 * (n2 / n3) * 0 - n9 * (n11 / n10) * 1 - (n4 + n9) * (n6 / n7) * rot5 = 0
rot5 = (-1) * (n11 / n10) * (n7 / n6) * n9 / (n4 + n9)
(m=>) d5 = 2 * t / | rot5 |

Given Parameters (Your choice !)

Reference
 Size Description
2
 n2 = [teeth] Bevel gear, fixed to wheel 1
3
 n3 = [teeth] Bevel gear, fixed to vertical shaft
4
 n4 = [teeth] Bevel gear, fixed to vertical shaft
6
 n6 = [teeth] Bevel gear, fixed to wheel 5
7
 n7 = [teeth] Bevel gear, freerunning on vertical shaft
8
 n8 = [teeth] Bevel gear, freerunning on horizontal shaft, which in turn is fixed to wheel 7
9
 n9 = [teeth] Bevel gear, freerunning on vertical shaft
10
 n10 = [teeth] Spur wheel, fixed to wheel 9
11
 n11 = [teeth] Spur wheel, fixed to pointer shaft
T
 t = [length units] Track width

Derived Parameters

Reference
 Size Description
1
 d1 = [units of t] Roadwheel, freerunning on axle
5
 d5 = [units of t] Roadwheel, freerunning on axle
© odts 2001